Tanita BC-41 User Manual



Please read this Instruction Manual carefully and keep

it handy for future reference.

BODY COMPOSITION ANALYZER

BC-418

INSTRUCTION MANUAL

3

Table of Contents

2



Table of Contents

••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

2



Advantages

•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

3



Safety Notes

•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

4

Caution Symbols

••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

4



WARNING

•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

4



CAUTION

••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

4



Maintenance

••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

5



General Instructions for Accurate Measurement

••••••••••••••••••••••

5

Usage Conditions

••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

5

Storage Conditions

•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

5

Power Source

•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

5

1. Product Assembly and Components

•••••••••••••••••••••••••••••••••••••••••••••••••••

6



Product Structure

••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

6



Rear View of Control Box

••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

7



Digital Display

••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

7



Membrane Switch

••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

8

2. Assembly Instructions

•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

9

3. Preparation for Use

••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

10



Connection and Installation

••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

10



Loading the Printer Paper Roll

•••••••••••••••••••••••••••••••••••••••••••••••••••••

11

4. Setting Date and Time

••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

12

5. Mode Selection

•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

13



Setting the number of printouts, the printout language, and the printout items

••••••••••••••

13



Setting the Original Mode

••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

14

6. Operating Instructions

•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

18



Body Composition Analysis

•••••••••••••••••••••••••••••••••••••••••••••••••••••••••

18



Weight Only Function

••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

21



Explanation of the Print Out

•••••••••••••••••••••••••••••••••••••••••••••••••••••••••

22

7. Clearing Paper Jams

••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

24



Components of the Printer Unit

•••••••••••••••••••••••••••••••••••••••••••••••••••

24



Clearing Paper Jams

••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

25

8. Troubleshooting

••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

26



Problem List

•••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

26



RS-232C Interface Instructions

••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

27

Technical Notes

••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

36



THE APPLICABILITY OF THE BMR REGRESSION
FORMULA AND ITS DIFFERENCES WITH THE OLD FORMULA

••••••••••

41



Product specifications

••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••••

43

Advantages

1. BIA is a simple, quick, and non-invasive means of measuring body composition, making it particularly useful

for group screenings.

2. The Tanita BC-418 Body Composition Analyzer calculates “body fat ratio,” “body fat mass,” “fat free mass,”

“estimated muscle mass,” and “Base Metabolic Rate” using data derived by the DXA method using BIA.

3. Through the use of 8 electrodes, the BC-418 Body Composition Analyzer makes it possible to show separate

body composition mass for the right arm, the left arm, the trunk, the right leg and the left leg.



WARNING

• Individuals with a Pacemaker or Other Internal Medical Devices
This equipment sends a weak electrical current through the body during measurement. Individuals
who have internally implanted medical devices, such as Pacemakers, should not use this equipment
due to the risk of malfunction to the device that may be caused by the weak electrical current.

• Inserting and Removing the Power Cord
To reduce the risk of electric shock or product damage, never insert or remove the power cord with
wet hands.

• Do not under any circumstances dismantle or alter the device, as this could result in electric shock or
injury as well as adversely affect the precision of measurements.

• To prevent fire hazard
Use only a correctly wired (100-240VAC) outlet, and do not use a multiple outlet extension cable.

• Measurements for physically disabled persons
Physically disabled persons should not attempt to take measurements alone, but instead should
have their caretakers assist them in using the device.



CAUTION

• Cross Contamination
The Body Composition Analyzer should be used with bare feet. Please be sure to clean the scale
platform with appropriate disinfectant after each use. Never pour any liquid directly on the scale
platform, as it may leak and cause internal damage. Use a soft cloth and appropriate ethyl alcohol
to wipe off platform. Do not wipe the platform with strong chemicals.

• Interpretation of Results
The data provided by this machine, as well as any supplementary information such as diet or
exercise programs based on this data, should be interpreted by a licensed professional.

• Please make sure you place the Weighing Platform on a level and stable surface. If the equipment
is used when the Weighing Platform is unstable because not all feet are on the surface, there may
be a risk of stumbling or inaccurate measurement.
Never jump on the Weighing Platform, there may be a risk of stumbling and malfunction of the
equipment.

• When handling printer unit, avoid any sharp edges.

• For the BC-418; Ensure you use the original AC adapter (MODEL: SA25-0535U). Using an AC
adapter other than the original one may cause malfunction.
Do not insert or remove the plug by the cable.



Maintenance

Since this equipment is accurately manufactured and adjusted, please observe the following instructions.

• Never disassemble the equipment as this may cause malfunction. Users must not disassemble or adjust this equipment.
Please inspect the equipment in accordance with the regulations in your country.

• Unplug the unit from the wall outlet when it will not be in use for long periods of time.

• In order to reduce the risk of a short circuit, please keep any liquid or metal objects (paper clips, etc.) away from the printer.

• Keep the electrodes clean by wiping them with disinfectant.

• Do not drop the unit, and avoid locations with constant vibration.

• Do not put this equipment in direct sunlight, close to heaters or near direct draughts from air conditioners.

• When transferred to any location where there is a difference of more than 20 degrees centigrade (40 degrees Fahrenheit),
wait 2 hours before using.

• When disposing of this unit, please do so in accordance with the prevailing regulations in each country.



General Instructions for Accurate Measurement

This equipment sends out a very weak electric current to measure impedance (electrical resistance) of the body. Therefore, in
principle, users need to use this equipment with bare feet. Moreover, since impedance fluctuates in accordance with the
distribution of body fluid, please observe the following instructions for accurate measurement.

• To prevent a possible discrepancy in measured values, avoid taking measurements after vigorous exercise until sufficiently

rested.

• To prevent inaccurately low body fat percentage measurements and other measurement errors, always hold both arms

straight down when taking measurements.

• As changes in body water and body temperature can have a major impact on measurements, measurements should be

made every day at the same time under similar conditions (always urinating before taking measurements, etc.) to get a
more accurate picture of the measurements over time.

• Ensure that your arms are not touching your side and that the inner thighs are not touching each other during

measurements; if necessary, place a dry towel between your arm and side and/or between your thighs.

• Also, make sure the soles of feet are free of excess dirt, as this may also act as a barrier to the mild current.

• False results may be reported after excessive food /fluid intake, or after periods of intense exercise.

* For further details, see the Technical Notes on page 36.

• This equipment is designed for the majority of the population leading healthy lives with a regular lifestyle. For people

suffering from sickness, or whose lifestyle is very different from the norm, it is recommended that the data from this
product should not be used as an absolute value, but rather as a reference to observe the rate change.
* For further details, see the Technical Notes on page 36.

• Measurement is sometimes impossible on a surface that is strongly vibrating. In this case, please move the equipment onto

a surface with little vibration.

• Do not take measurements while using transmitters, such as mobile phones, which may affect readings.

Safety Notes

54

Caution Symbols

Thank you for purchasing this precision crafted Tanita product. For optimum performance and safety, please familiarize
yourself with the Caution Symbols below. These symbols are designed to alert the user to potential hazards when using this
equipment. Ignoring these Caution Symbols may result in serious injury, or damage to the product.
Please be sure to review before proceeding with the INSTRUCTION MANUAL.

Temperature Range for Use : 0°C / 35°C
Relative Humidity : 30% / 80% (without condensation)

Temperature Range of Environment : -10°C / 50°C
Range of Relative Humidity : 10% / 90% (without condensation)
To avoid malfunctions, avoid storing the equipment where there is direct sunlight, significant temperature
changes, the risk of dampness, a large amount of dust, in the vicinity of fires, or where there is the risk of
receiving vibrations or shocks.

Value Range

100~240VAC

50/60Hz

550mA

Voltage Range

Frequency Range

Electric Current Range

BC-418

Model Name

<Usage Conditions>

<Storage Conditions>

<Power Source>

This symbol indicates the possibility of serious injury if the product is
mishandled or instructions are ignored.

This symbol indicates the possibility of physical injury or equipment
damage if instructions are ignored.

This symbol indicates general precautions that should be taken when using
this product.



WARNING



CAUTION



6

1.Product Assembly and Components

Printer Paper

Paper Width：58mm
Paper Roll Diameter：Maximum 55mm

 Product Structure

Please verify that the following components are in the package.

Instruction Manual

(Technical Notes)

Bottom Cover

Accessories

7

 Rear View of Control Box

Column Attachment

Screws

Bottom Cover

Attachment Screws

 Paper Dispenser Cover
 Printer Cover
 Control Panel
 Digital Display
 Left-hand grip
 Right-hand grip
 Column
 Anterior Electrodes
 Posterior Electrodes
 Level Gauge
 Adjustable feet



















Control Box

AC Adapter

cable

Platform





RS-232C

RS-232C Port

 Digital Display

CLOTHES

ATHLETIC

MALE

WEIGHT

FEMALE

STEP ON

kg

cm

ft.in

AGE

% FAT

lb

Body weight mark

Indicates that the device is being
used to measure body weight

Clothes weight mark

Indicates that the weight of
clothes is being subtracted

Gender mark (male)

Indicates that the user is male

Gender mark (female)

Indicates that the user is female

Athlete mark

Indicates that the user is an
“athlete”

Ready mark

Indicates that the device is
ready to begin measurements

Measurement unit mark (kg)

Indicates that the weight is
shown in kilograms

Measurement unit mark (lb)

Indicates that the weight is
shown in pounds

Unit of height (cm)

Indicates that the height is
shown in centimeters

Unit of height (ft. in)

Indicates that the height is
shown in feet and inches

Age mark

Indicates that the figure shown
is the user’s age

Body fat percentage

Indicates that the figure shown
is the body fat percentage

8

 Membrane Switch

R

R

L

L

%Body Fat Range : 1%~75%
%Body Fat Increments : 0.1%
Max 200kg / 440lb
e=d= 0.1kg / 0.2lb
Min 2kg / 4lb
T= -200kg /-440lb
Operation Temperature Range 0 / +35 C

Feed Key

Advances the print paper.

ON/OFF Key

Turns the power on or off.

Clothes Weight Setting Key

Sets the clothes weight.
Even if the user is dressed, weight minus the weight of
clothes can be measured.
(Body Composition Analysis mode)

Weight Only Key

Measures body weight only.

kg/lb Key

Measures changing kg/lb only.
* Not available on analyzers with “kg only”

specifications

CE Key

Clears entries.

Body part data display keys

Used to display the measurement
results for the right arm, left arm,
right leg, left leg and trunk

Body Type Keys

To select the appropriate body type

Tanita defines “athlete” as a person involved in intense physical activity of at least 10
hours per week and who has a resting heart rate of approximately 60 beats per minute
or less. Tanita’s athlete definition includes “lifetime of fitness” individuals who have
been fit for years but currently exercise less than 10 hours per week.

Tanita’s athlete definition does not include “enthusiastic beginners” who are making a
real commitment to exercising at least 10 hours per week but whose bodies have not yet
changed to require the Athlete mode.

Please see Technical Notes booklet for further explanation.

Numerical Keys

Inputs numerical values.

Time Set Key

Sets the date and time.

CLOTHES

ATHLETIC

MALE

WEIGHT

FEMALE

STEP ON

kg

cm

ft.in

AGE

% FAT

lb

Digital display

These marks are not present
on models having no display
switch key.

9

2.Assembly Instructions

Bottom Cover

Column
Attachment

Screws
Bottom Cover
Attachment Screws

Remove the Bottom Cover.

Insert the two cables from the column into the holes on

the Weighing Platform.

Tighten the four Column Attachment Screws and attach

the column to the Weighing Platform.

Connect the two cables from the column to the Weighing

Platform as shown in the illustration and replace the

Bottom Cover using the two Bottom

Cover Attachment Screws. When

replacing the Bottom Cover, please

place the cables in the right position

so that they will not get caught

between the cover and the Weighing

Platform. This may damage the

cables.

 How to Attach the Column to the Weighting Platform

11

 Connection and Installation

3.Preparation for Use

For accurate measurement, place the Weighing Platform on as flat a surface as possible and adjust the level with the adjustable feet so the bubble in

the level gauge is in the center of the frame.



CAUTION

Make sure you place the Weighing Platform on a stable level surface and adjust the level with the adjustable feet. If the
Weighing Platform is not stable because not all the feet are on the surface, for example, there is a risk of stumbling or
inaccurate measurement.

 Connection of Plugs

1. Insert the plug from the AC adapter into the DC jack on the back of the weighing platform.

2. Connect the cable and the AC adapter and insert the plug on the cable into the wall outlet.



WARNING

•To avoid electric shock, do not insert or remove the plug with wet hands.

•To avoid electric shock, do not use the equipment near water.



CAUTION

•To avoid measurement error, do not measure while using equipment that generates radio waves,
such as mobile phones.

Level Gauge
Check

DC Jack for AC Adapter

Adjustable feet

10

 Loading the Printer Paper Roll



CAUTION

Please change the paper roll when red lines appear along the sides of the paper.



1. Turn the equipment on by pressing the [ ]
key.

“P.End” will flash in the middle of the display.
This means that there is no printer paper.
* When you do not have any printer paper to replace

the old roll, press the [ ] key. “P.End” will
disappear and you can continue measurement.

2. Remove the Paper Dispenser Cover.

When you lift up the Paper Dispenser Cover from the
back of the Control Box, it can be easily removed.

3. Cut off the end of the printer paper where the
glue is (about 3 cm) in a straight line.



Please make sure to cut off the part with the
glue because the glue may hinder the paper
feeding through the printer.

4. Insert the printer paper into the slit.

The printer paper is automatically rolled up and the
edge of the paper is cut automatically.
Please remove the cut paper.



Please make sure you insert the printer paper
straight into the slit.

5. Insert the catches of the Paper Dispenser Cover
into the guide holes.

* If a paper jam occurs, please refer to P. 25.

ON

OFF

WEIGHT

CLOTHES

MALE

FEMALE



ATHLETIC

STEP ON

3cm

kg

lb

cm

ft.in

AGE

% FAT

12 13

 Setting the date and time

4.Setting Date and Time







1. Push the [ ] key.

The entire display will begin to flash, and then the
clothes weight input screen will appear.

2. Push the [ ] key.

The date and time input screen will appear.
The upper row of numbers show the year, the middle
row the month and day, and the bottom row the time
(hours and minutes).

If no changes are to be made, press the [ ] key again.

3. Input the present date and time.

Input the appropriate numbers, beginning with the
top row, in the flashing space.
Example: To input May 1, 2002, 6:03 p.m., press in
order the following keys:

* If you make an error while inputting a number, press the

[ ] key.

This will return you to the previous input space.

4. Press the [ ] key.

The date and time are set, and the clock function is
running.
The display will now return to the step prior to
entering this mode.

* The clock function is backed up by the rechargeable battery,

but natural electric discharge of the rechargeable battery

may occur if the device is not in use for an extended period

(more than 2 weeks); this will clear the settings, making it

necessary to reset the date and time.

TIME SET

308110502002

TIME SET

TIME SET

ON

OFF



The printer function is ON in the display shown below.

5.Mode Selection

 Setting the number of printouts, the printout language, and the printout items











Set the functions (modes) that you want this equipment to start with. The selected modes will be automatically recorded.
If it is not necessary to change the settings, the equipment will start up when you simply press the [ ] key.

ON

OFF

1.

While holding down the [0] key, press the [ ]
key.

Release the keys after “Prt-1” is displayed on the
screen.

2. Select the number of print outs

Using the numerical keys, enter the quantity of print
outs desired.
The maximum number is nine.

[1]~[9] : Quantity of print outs
[0] : No printout

3. Language Selection



If“0” is selected at step 2, you cannot preset the
language.

The display will automatically change to the language
selection screen. The currently selected language will
be displayed as a number.

Example: (LNG-1) means English.

Select the language desired using the numerical keys.

[1] : English
[2] : French
[3] : German
[4] : Italian
[5] : Spanish

4. Printing selection

Printing contents are selected from numerical keys.

[0] : Short
[1] : Long

5. The display will automatically change to the
measurement screen after all the input has been
completed.

If further change to the print settings is desired,
please turn off the equipment and follow steps 1 - 4
above.

ON

OFF



The equipment will start up with these settings next time you use it.

Select the number of print outs (0 - 9) and language. (English, French, German, Italian, Spanish)

WEIGHT

CLOTHES

MALE

FEMALE

ATHLETIC

STEP ON

WEIGHT

CLOTHES

TIME SET

~

TIME SET

MALE

FEMALE

ATHLETIC

STEP ON

WEIGHT

CLOTHES

MALE

FEMALE

ATHLETIC

STEP ON

WEIGHT

CLOTHES

MALE

FEMALE

ATHLETIC

STEP ON







kg

lb

cm

ft.in

AGE

% FAT

kg

lb

cm

ft.in

AGE

% FAT

kg

lb

cm

ft.in

AGE

% FAT

kg

lb

cm

ft.in

AGE

% FAT

WEIGHT

CLOTHES

MALE

FEMALE



ATHLETIC

STEP ON

WEIGHT

CLOTHES

~

~

MALE

FEMALE

ATHLETIC

STEP ON

WEIGHT

CLOTHES

MALE

FEMALE

ATHLETIC

STEP ON

WEIGHT

CLOTHES

MALE

FEMALE

ATHLETIC

STEP ON

WEIGHT

CLOTHES

MALE

FEMALE

ATHLETIC

STEP ON









kg

lb

cm

ft.in

AGE

% FAT

kg

lb

cm

ft.in

AGE

% FAT

kg

lb

cm

ft.in

AGE

% FAT

kg

lb

cm

ft.in

AGE

% FAT

kg

lb

cm

ft.in

AGE

% FAT

WEIGHT

CLOTHES

MALE

FEMALE

ATHLETIC

STEP ON

kg

lb

cm

ft.in

AGE

% FAT

14 15



The equipment will start up with these settings next time you use it.

This process is utilized to select whether or not you use the target body fat ratio function. (See the printout sample
on page 16.)







<HINT! >

The target body fat ratio function is deactivated when this product is shipped from factory.

 Setting the Original Mode

1.

Press the key while holding down the key.

[0] : The target body fat ratio function is deactivated
[1] : The target body fat ratio function is activated



If the number of print outs is set to “0” during
the process of “Setting the Number of Print Outs
and Language” on page 13, you cannot preset
this item.

2. After the input is completed, the display will
automatically change to the measurement
display.

ON

OFF

CLOTHES

kg

lb

cm

ft.in

AGE

% FAT

kg

lb

cm

ft.in

AGE

% FAT

kg

lb

cm

ft.in

AGE

% FAT

or

WEIGHT

CLOTHES

MALE

FEMALE

ATHLETIC

STEP ON

WEIGHT

CLOTHES

MALE

FEMALE

ATHLETIC

STEP ON

WEIGHT

CLOTHES

MALE

FEMALE

ATHLETIC

STEP ON







16 17

ON

[1]

Goal Setter Mode Print Out

STANDARD

Input

ATHLETIC

STANDARD

ATHLETIC

OFF

[0]

Short

[0]

Printing selection

Long

[1]

TARGET BF 00%

ON

[1]

STANDARD

ATHLETIC

STANDARD

ATHLETIC

OFF

[0]

TARGET BF 00%

<Printing selection and Goal Setter Mode>

For this Printing Selection, please refer to the page 13.

For this Goal Setter Mode, please refer to the page 14.

BODY TYPE
GENDER
AGE
HEIGHT
WEIGHT
BMI
BMR

FAT%
FAT MASS
FFM
TBW
DESIRABLE RANGE
FAT%
FAT MASS

TARGET BF% is :

Predicted weight :

Predicted fat mass :

FAT TO GAIN:

STANDARD

MALE

34

179 cm

73. 3 kg

23. 9
7294 kJ
1743 kcal

13. 1 %

9. 6 kg

63. 7 kg

46. 6 kg

8–20 %

5. 5–15. 9 kg

IMPEDANCE
Whole Body
Right Leg
Left Leg
Right Arm
Left Arm

Segmental Analysis
Right Leg
Fat%
Fat Mass
FFM
Predicted MuscleMass

Left Leg
Fat%
Fat Mass
FFM
Predicted MuscleMass

Right Arm
Fat%
Fat Mass
FFM
Predicted MuscleMass

Left Arm
Fat%
Fat Mass
FFM
Predicted MuscleMass

Trunk
Fat%
Fat Mass
FFM
Predicted MuscleMass

551 Ω
212 Ω
214 Ω
292 Ω
309 Ω

8.9 %

1.1 kg

11.5 kg

10.9 kg

10.1 %

1.2 kg

11.0 kg

10.4 kg

14.0 %

0.6 kg

3.6 kg

3.4 kg

15.4 %

0.6 kg

3.5 kg

3.3 kg

15.0 %

6.0 kg

34.1 kg

32.8 kg

20%

79. 6 kg

15. 9 kg

6. 3 kg

TANITA

BODY COMPOSITION

ANALYZER

BC—418

Consul t your physician
before beginning any
weight management pro–
gram. Tanita is not re–
sponsible for deter–
mining your target BF%.

Sample

21⁄SEP⁄2002 19:29

This section prints the both the
body type and body
composition data of the
current user.

This section calculates the
amount of fat that should be
lost or gained to achieve the
Target BF% (preset by the user
and health care professional).

The measurement data for
each body part – the predicted
muscle mass, the fat mass, and
the body fat percentage – are
printed out in this portion.





19

Posterior Electrodes

Anterior Electrodes



1. Turn on the Power.

Press the [ ] key.
“0.0” will appear on the upper portion of the display.

2. Enter Clothes Weight.

Enter clothes weight using the numerical keys.
Example: if the clothes weight is 2.0 kg, press [2], [.]
and then [0].
When the data input is completed, the data will be
displayed as a minus number.

3. Select the Body Type.

Select the Body Type from Standard Male, Standard
Female, Athletic Male and Athletic Female. Please use the
Athletic key when the user is 17 years or older and also
meets the following criteria.

See page 8 for Tanita’s definition of “Athlete.”

4. Enter Age.

* If the user is 32 years old or younger.

Example: Press [3] and [2].

* If the user is 9 years old or younger

Example: press [0] and [9].

* If ages 16 or less are entered, even if Athletic is

selected for the Body Type, it will be automatically
changed to Standard.

5. Enter Height.

Example: If the user’s height is 172 cm, please press [1], [7]
and then [2].

ON

OFF

6.Operating Instructions

 Body Composition Analysis











18

6. Set the Target Body Fat Ratio.

After you input the height, “GOAL” will
automatically flash on the display. Input the target
body fat ratio desired using the numerical keys.
Example: 16% = Press [1] and [6].

9% = Press [0] and [9].

* If the number of print outs is set to “0”, nothing will

be displayed.

* If the target body fat ratio is set to OFF, the target

body fat ratio will not be printed out.



• Before you start a body weight management
program and set the appropriate personal
body fat ratio, please consult your doctor.
Tanita is not responsible for setting the
appropriate target body fat ratio for specific
individuals.

• For details of the desirable body fat
percentage, please refer to the Technical Notes.
Male athletes may wish to select a single digit
body fat percentage as their target. However,
this is not recommended for Standard Adults, in
particular women, who should avoid becoming
excessively lean. Always consult a doctor about
the target body fat percentage most suitable for
your body type.



• Do not step on the Weighing Platform until the
target body fat ratio setting has been
completed because the power may be
automatically turned off or the measurement
may be inaccurate.

* If you want to change the settings, please press the

[ ] key and the procedure will go back to the
former step. Please re-enter the data.

7. After “88888” is displayed on the upper portion
of the display, a flashing arrow will appear next
to .

8. Start Measurement.

Step on the Weighing Platform with bare feet so they
touch the electrodes. Stand in a stable position without
bending your knees.



• Do not use the hand grips, as you will only be
measuring your body weight this time.

STEP ON




This explains the procedure when the printer function is turned on. Please be aware that the display may be
different if the number of printouts is set to [0].

• Do not wipe the equipment with corrosive chemicals (gasoline, cleaner, etc.). Please use a neutral
detergent to clean the equipment.

• When the equipment has been transferred to any location where there is a temperature difference of
20˚C or more, wait for at least two hours before using it.

• In taking measurements, please keep the person away from the unit, who uses transmitters such as a
mobile phone avoid causing margin errors.

Male Female

STANDARD

ATHLETIC

WEIGHT

CLOTHES

MALE

FEMALE



ATHLETIC

STEP ON

WEIGHT

CLOTHES

~

STANDARD

ATHLETIC

~

MALE

FEMALE

ATHLETIC

STEP ON

WEIGHT

CLOTHES

MALE

FEMALE

ATHLETIC

STEP ON

WEIGHT

CLOTHES

MALE

FEMALE

ATHLETIC

STEP ON







kg

lb

cm

ft.in

AGE

% FAT

kg

lb

cm

ft.in

AGE

% FAT

kg

lb

cm

ft.in

AGE

% FAT

kg

lb

cm

ft.in

AGE

% FAT

WEIGHT

CLOTHES

MALE

FEMALE

ATHLETIC

STEP ON

WEIGHT

CLOTHES

~

MALE

FEMALE

ATHLETIC

STEP ON



kg

lb

cm

ft.in

AGE

% FAT

kg

lb

cm



ft.in

AGE

% FAT

WEIGHT

CLOTHES

MALE

FEMALE

ATHLETIC

STEP ON



kg

lb

cm

ft.in

AGE

% FAT

~

WEIGHT

CLOTHES

MALE

FEMALE



ATHLETIC

STEP ON

kg

lb

cm

ft.in

AGE

% FAT

1. After turning on the unit, press the [ ] key.

After a momentary display check, “0.0” will appear
on the LCD. If measuring units need to be changed,
do so at this time by pressing the [ ]key.
An arrow on the LCD will follow the selection of
weighing units.

2. Weight Measurement.

Step on the weighing platform. Weight will be
displayed on the LCD.

3. When measuring is complete, press the [ ]
key to turn off the power.



• No printer is available when measuring
weight only.

• If body composition analysis is desired, turn
the unit off and then on, using the [ ]
key.

Important Note: There is no automatic weight lock

function.

ON

OFF

ON

OFF

 Weight Only Function







21

9. Taking Measurement.

Step on the weighing platform in bare feet. Make sure heels
are placed on the posterior electrodes, and the front part of
the feet are in contact with the anterior electrodes.

10.Measure the Impedance.

When the grips are grasped with both hands,
will appear at the bottom of the display and the
impedance measurement will begin.

The marks will disappear one by one during the
measurement; after five full cycles, the measurement will be complete.



•

Grab the grips (two locations) only after the body
weight figure on the display has stabilized.

• Do not step off the Weighting Platform until
the “ ” symbols disappear completely.

• In cases when measurements of the body fat ratio
or the quantity of fat are abnormally small or the
error message (E01) is shown on the display, the
probable reason is that the soles of the feet and the
electrodes are not in full contact. Make sure you
step on the Weighing Platform so there is contact
between the electrodes and the soles of your feet.
If the problem is not solved this way, it is possible
that the soles of the feet have calluses and the
resistance is too great. Therefore, place about 0.5
ml of water on each of the four electrodes where
the feet touch before measurement.

11.Measurement Is Completed.

Once the body weight and impedance measurements have
been completed, the overall body fat percentage will be
shown at the bottom of the display and a buzzer will sound.
If the printer is ON, the measurement results will be printed out.
* With regard to the measurement result, please refer to P. 22.

If the printer is OFF, the measurement results (predicted
muscle mass, fat mass, and body fat percentage) for each
body part can be displayed using the ten-key pad.
Select the number of the desired body part on the ten-key pad.

[4]: Left arm
[6]: Right arm
[0]: Left leg
[.]: Right leg
[5] and [2]: Trunk

* See page 13 for details on printer settings.
Step off the Weighing Platform.

12.When You Continue to Measure.

After printing is completed, go back to step 3.
Measure by entering the data in the same procedure.

13.Finish Measurement.

Press the [ ] key and turn off the power.

ON

OFF

20

WEIGHT

Right legLeft leg

Right armLeft arm

Trunk

CLOTHES

MALE

FEMALE

ATHLETIC

STEP ON

WEIGHT

CLOTHES

MALE

FEMALE

ATHLETIC

STEP ON

L

L

WEIGHT

CLOTHES

MALE

FEMALE

ATHLETIC

STEP ON

kg

lb

cm

ft.in

AGE

% FAT

WEIGHT

CLOTHES

MALE

FEMALE



ATHLETIC

STEP ON

WEIGHT

CLOTHES

MALE

FEMALE



ATHLETIC

STEP ON

WEIGHT

CLOTHES

MALE

FEMALE



ATHLETIC

STEP ON

kg

lb

cm

ft.in

AGE

% FAT

kg

lb

cm

ft.in

AGE

% FAT

kg

lb

cm

ft.in

AGE

% FAT

kg

lb

cm

ft.in

AGE

% FAT

R

R

kg

lb

cm

ft.in

AGE

% FAT

20-39

40-59

60-79

20-39

40-59

60-79

0% 10% 20% 30% 40%

2322

 Explanation of the Print Out

BODY TYPE
GENDER
AGE
HEIGHT
WEIGHT
BMI
BMR

FAT%
FAT MASS
FFM
TBW
DESIRABLE RANGE
FAT%
FAT MASS

TARGET BF% is :

Predicted weight :

Predicted fat mass :

FAT TO GAIN:

STANDARD

MALE

34

179 cm

73. 3 kg

23. 9

7294 kJ

1743 kcal

13. 1 %

9. 6 kg

63. 7 kg

46. 6 kg

8 – 20 %

5. 5– 15. 9 kg

IMPEDANCE
Whole Body
Right Leg
Left Leg
Right Arm
Left Arm

551 Ω
212 Ω
214 Ω
292 Ω
309 Ω

20%

79. 6 kg

15. 9 kg

6. 3 kg

TANITA

BODY COMPOSITION

ANALYZER

BC—418

Consul t your physician
before beginning any
weight management pro–
gram. Tanita is not re–
sponsible for deter–
mining your target BF%.

Sample

21⁄ SEP⁄ 2002 19:29

Segmental Analysis
Right Leg
Fat%
Fat Mass
FFM
Predicted MuscleMass

Left Leg
Fat%
Fat Mass
FFM
Predicted MuscleMass

Right Arm
Fat%
Fat Mass
FFM
Predicted MuscleMass

Left Arm
Fat%
Fat Mass
FFM
Predicted MuscleMass

Trunk
Fat%
Fat Mass
FFM
Predicted MuscleMass

8.9 %

1.1 kg

11.5 kg

10.9 kg

10.1 %

1.2 kg

11.0 kg

10.4 kg

14.0 %

0.6 kg

3.6 kg

3.4 kg

15.4 %

0.6 kg

3.5 kg

3.3 kg

15.0 %

6.0 kg

34.1 kg

32.8 kg

NOTE:Please refer to the Technical Notes for details.



Please consult your doctor before you start a body weight management program. Tanita is not responsible for the
target body fat ratio.

BMI:Body Mass Index is a height to weight

ratio, and is calculated by the following
formula:

Weight (kg)
Height (m2)

Desirable Range 18.5 - 24.9

IMPEDANCE:Impedance reflects the body’s
inherent resistance to an electrical current.
Muscle acts as a conductor of the electrical
current, adipose tissue acts as a resistor.

BMR:Basal Metabolic Rate represents the
total energy expended by the body to
maintain normal functions at rest such as
respiration and circulation.

FAT MASS:Total weight of fat mass (in kg ,
lb) in the body.

FAT%:The percentage of total body weight
that is fat.

FFM:Fat Free Mass is comprised of muscle,
bone, tissue, water, and all other fat free
mass in the body.

PW:Predicted weight
Calculated weight for the given Target
BF%.

FAT TO LOSE/GAIN:

Calculated fat mass to lose or gain to
achieve the Predicted Weight.

PFM:Predicted fat mass
Caluculated fat mass for the given Target
BF%.

TBW:Total Body Water is the amount of
water (expressed as lb, kg, or st.lb) retained
in the body. TBW is said to comprise
between 50% - 70% of total body weight.
Generally, men tend to have higher water
weight than women due to a greater
amount of muscle.

PMS:Predicted Muscle Mass
means bone-free lean tissue mass (LTM)

Body Fat Ranges for Standard Adults

Age

Underfat Healthy Overfat Obese

Underfat Healthy Overfat Obese

Female

Male

* As reported by Gallagher,et al., at NY Obesity Research Center.

To determine the percentage of body fat that's appropriate for your body,consuit your physician.

Underwight

BMI ＜ 18.5

18.5 ≦ BMI ＜ 25
25 ≦ BMI ＜ 30
30 ≦ BMI ＜ 35
35 ≦ BMI ＜ 40

BMI ≧ 40

Normal Range

Pre obese

Obese CLASS l

Obese CLASS ll

Obese CLASS lll

Based on NIH/WHO BMI Guidelines



CAUTION

Please pay careful attention to avoid injury from the sharp edge.
Please turn off the machine before clearing Paper jams.

1. Remove the Paper Dispenser Cover.

If you lift up the Paper Dispenser Cover from the
back of the Control Box, it can be easily removed.

2. Remove the Printer Cover.

As shown in the illustration, from the front side of the
Control Box, use a finger to lift up the Printer Cover.



The Printer Cover is firmly fixed by catches.
Please make sure not to drop the Control Box
when you remove the Printer Cover.

3. Lift up the Automatic Cutter Unit.

From the front side of the Control Box, lift up the
Automatic Cutter Unit with a finger.

4. Raise the Paper Release Lever and remove the
jammed paper.

Remove the printer roll paper and the jammed paper.

5. Return the Paper Release Lever, the Automatic
Cutter Unit and the Printer Cover to the normal
position.

Insert the catches of the Printer Cover into the guide
holes of the Control Box and push it down slowly
while pressing the catches on both the left and right
hand sides until a click is heard.



Failure to press down the Paper Release Lever
will result in continuous feeding of the printer
paper without it being cut automatically.

6. Return the printer paper roll.

Return the printer paper roll by following the
procedure in P. 11 [Loading Printer Paper Roll].

7. Return the Printer Dispenser Cover to the proper
position.

Press the Printer Dispenser Cover down slowly as the
catches of the cover go into the guide holes. P. 11.

Auto-cutter
Unit

Paper Release
Lever

25

 Clearing Paper Jams

7.Clearing Paper Jams

24

 Components of the Printer Unit

Automatic Cutter Unit Printer Paper Outlet

Paper Release Lever

* This is a picture of the Control Box without the Printer Dispenser Cover and the Printer Cover, looking down

from above.

26

If problems occur, please refer to the following instructions before you ask for repairs.

 Problem List

8.Troubleshooting

Problem Solution

Nothing appears on the display after
pushing [ ] key.

ON

OFF

• Please confirm that the Control Box is properly connected to the AC
Adapter and the AC Adapter is properly connected to the cable.

E-01 is displayed.

• E-01 is displayed when the impedance shows an abnormal value
compared to height and weight.
Please make sure that measurement was carried out with bare feet, the
electrodes or the soles of the feet were clean, and the feet were correctly in
contact with the electrodes. If the feet are dry or have calluses, place water on
the electrodes before stepping on the unit.

• It is possible that the body fat ratio exceeds the measuring capacity.
Please stop measuring.

E-02 is displayed and the reading of
the trunk cannot be obtained.

• This sign is displayed when the body fat percentage of the trunk is too
low and is off the measureable range.

• Please refer to the readings of other parts for the body fat.

27

RS-232C Interface Instructions

This section describes the interface for outputting the BC-418 Body Composition Analyzer measurement results as

RS-232C signals to personal computers and other external devices.



CAUTION

Only connect IEC950-compliant computers to the BC-418.

•Connection example Always use a reverse cable when connecting to an external computer.

 Specifications  Signal lines and connection methods

Communication Standard

EIA RS-232C Compatible

Asynchronous Transmission

4800 baud

8 bits

None

1 bit

CR+LF

Communication Method

Signal speed

Data bit length

Parity

Stop bit

Terminator

Terminal number Signal name

2 RXD
3 TXD
5 GND

1.
RXD

TXD

GND

2.RXD

3.TXD

4.

5.GND

Personal computer or
other device

•An RS-232C connector (D sub 9-pin male) is located in the lower center on the back of the control box.

•Use an RS-232C cross cable when connecting to a personal computer or other device.

D sub 9-pin female

RS-232C cross cable

RS-232C connector (D sub 9-pin male)

E-11 is displayed.

• E - 11 is displayed when there is a loose connection between the control
box and the weighing platform.

• Confirm that none of connections between the scale and control box are
loose or unplugged.

•

There may be excessive vibration which will disturb the measurement process.

E-12, 13 or 14 is displayed.

• The equipment requires readjustment.

E-16 is displayed.

• Measurement is not possible because impedance is unstable. In order to
improve electrical conductivity, please clean the soles of the feet or
place water on the electrodes before using the equipment.

No print out

• Please confirm the number of print outs selected is more than 0. (See P. 13)

• Please confirm that the correct brand of paper is used.

• Please confirm that the printer paper roll is placed in the correct position.

• Please confirm that the printer paper is not jammed.

The printer paper does not come out.

• Please confirm the printer paper is not jammed.

P.End is displayed and the equipment
is incapable of taking a measurement.

•

The printer paper is used up. Please put in a new printer paper roll. (See P.11)

• Please confirm that the printer paper is being advanced properly.

•

Please make sure that the Paper Release Lever is not in the “Up” position. (See P. 25)

---- is displayed.

• It is possible that the maximum weight capacity has been exceeded.
Please stop measuring.

uuuu is displayed.
The power has turned off during measurement.

•

Do not stand on or put things on the Weighting Platform before starting measurement.
Start measurement after confirming there is nothing on the Weighing Platform.

Feed Key is not functioning.

• It is possible that the number of print outs selected is 0 or the Weight
Scale Mode has been selected. Please select the Body Fat Measurement
Mode and select a number larger than 0 for the number of print outs.

• Transmission data will be output after measurements regardless of the status of the
personal computer or other device at the receiving end. For that reason, the
personal computer or other device to which data will be transmitted must be put in a
reception-ready status before measurement.



CAUTION

1 .Output data items

29

 Transmission data



Data will not be output if the [ ] key is used to switch to the body weight only mode.



Calculations are made using 1kcal = 4.184kJ.

Left leg
Right arm
Left arm

Date

Time

Body type

Gender

Height

Weight

Body fat percentage

Fat mass

Fat free mass

Body water mass

BMI

BMR

Impedance

Right leg

Left leg

Whole body
Right leg

Body fat percentage
Fat mass
Fat free mass
Predicted muscle mass
Body fat percentage
Fat mass
Fat free mass

Predicted muscle mass

Right arm

Body fat percentage

Fat mass
Fat free mass
Predicted muscle mass

Left arm

Body fat percentage
Fat mass
Fat free mass
Predicted muscle mass

Trunk

Body fat percentage
Fat mass
Fat free mass
Predicted muscle mass

“dd/mm/yy” (date/month/year)

Data

kg mode lb mode

Byte Length

“hh:mm” (hour:minutes)

“dd/mm/yy” (date/month/year)

“hh:mm” (hour:minutes)
0: standard 2: athlete 0: standard 2: athlete
1: male 2: female 1: male 2: female

Age

Output data (ASCII code)

28

2 .Output data format

Measurement data will be output in the following format.

• A comma (,) is used as a separator between data items.

• The terminators marking the end of data are CR (ASCII code: ODH) and LF (ASCII code: OAH).

• If the digits in the data do not reach the stipulated length for fixed length data, the data will be right­justified for output, with a zero (0) (ASCII code: 30H) entered in any empty spaces.

Comma

d d ／mm／y y , h h : mm, x , x ,

xx,

xxxxx,

Date Time

Height

Body type

Gender

Age

Comma

xxx. x

xx. x,

xxx. x, xxx

xxx

xxx

xxx

xxx

xxx

.x,

,

xxx. x,

Weight

Fat mass

Fat free mass

Body water mass

Body fat percentage

xxx. x,

Fat free mass

xxx. x,

Fat mass

xx. x,

,

,

,

,

,

,

Body fat percentage

Right leg

Comma

x xx .x , xxxxx ,

BMI

Whole body impedance

Right leg impedance

Left leg impedance

Right arm impedance

Left arm impedance

BMR

xxx. x

Predicted muscle mass

Comma

xxx. x,

Fat free mass

xxx. x,

Fat mass

xx. x, ,

Body fat percentage

Left leg

xxx. x

Predicted muscle mass

Comma

CR LF

Terminator

xxx. x,

Fat free mass

xxx. x,

Fat mass

xx. x, ,

Body fat percentage

Right arm

xxx. x

Predicted muscle mass

Comma

xxx. x,

Fat free mass

xxx. x,

Fat mass

xx. x, ,

Body fat percentage

Left arm

xxx. x

Predicted muscle mass

Comma

xxx. x,

Fat free mass

xxx. x,

Fat mass

xx. x,

Body fat percentage

Trunk

xxx. x

Predicted muscle mass

Comma

D? : Confirm current setting

D0 : Set clothing weight (5-byte fixed length)

D1 : Set gender male = 1 female = 2

D2 : Set body type standard = 0 athlete = 2

D3 : Set height (5-byte fixed length)

D4 : Set age (2-byte fixed length)

D6 : Set Target BF (2-byte fixed length)

 Control Commands

When in Remote mode, the body fat analyzer may be operated remotely by sending control commands from a host.

 Error Codes

If an error occurs, the body composition analyzer will send an error code to the host.

*All fixed-length data right aligned. Enter for blanks.

0

U? :

Confirm current setting

U0: Use cm/kg mode

U1: Use in/lb mode

LFCR1U

LFCR0U

LFCR?U

commands

U

LFCRXX6D

LFCRXX4D

LFCRXXXXX3D

LFCRX2D

LFCRX1D

LFCRX.XXX0D

LFCR?D

commands

D

G1: Start measuring body fat

G2: Measure weight only

LFCR2G

LFCR1G

commands

G

CHR$(01FH): Reset settings

CHR$(01EH): Cancel measurement

LFCRCHR$(01EH)

LFCRCHR$(01FH)

Special

commands

E00 : Attempted to start measuring without completing settings

E01 : Error in calculating body fat percentage

EXX :other error ’ body fat analyzer switches off

LFCRXXE

LFCR10E

LFCR00E

*See p.26 "7. Troubleshooting" for details of errors.

31

Output (Fat Monitor Mode) Format

Remote Mode

All types of data may be entered by connecting the BC-418 to a PC and switching to Remote mode.

 Switching to Remote Mode

1. When the unit is switched off, press the [ ]
and [ ] keys simultaneously.



Note

The default setting is off.

2. Press [0], [8].

3. Switch Remote mode on and off by pressing [1]
or [0].

[1] : Enables Remote mode
[0] : Disables Remote mode

4. Press [ ] to confirm.

5. Push the [ ] key.

Only "r S" will appear (standby display).

Note

To switch off Remote mode, start
from the beginning again and
select "OFF" at Step 3.

ON

OFF

ON
OFF







30

WEIGHT

CLOTHES

MALE

FEMALE

ATHLETIC

STEP ON

WEIGHT

CLOTHES

MALE

FEMALE

ATHLETIC

STEP ON

WEIGHT

CLOTHES

MALE

FEMALE

ATHLETIC

STEP ON

kg

lb

cm

ft.in

AGE

% FAT

kg

lb

cm

ft.in



AGE

% FAT

kg

lb

cm

ft.in

AGE

% FAT

WEIGHT

CLOTHES

MALE

FEMALE

ATHLETIC

STEP ON

WEIGHT

CLOTHES

MALE

FEMALE

ATHLETIC

STEP ON

kg

lb

cm

ft.in





AGE

% FAT

kg

lb

cm

ft.in

AGE

% FAT

Host . /body composition analyzer

*Gender, body type, height and age must be entered.

*Once all the necessary items of data have been entered, the unit will determine on the basis of age and gender whether to switch to Athlete or Standard mode.

Hence even if you choose Athlete mode, the unit may switch to Standard mode.

*If starting in Weight Only mode, only tare weight needs to be set.

LFCR?D

Set body type

5

Ex: standard

Host . /body composition analyzer

LF

CR02D

Set height

6

Ex: 179cm

Host . /body composition analyzer

LF

CR971003D

Set age

7

Ex: 34

Host . /body composition analyzer

LF

CR434D

Confirm settings

9

Host , . body composition analyzer

LF

CR2D

Host ,. body composition analyzer

LF

CR!2D

If commands accepted

If settings incorrect

Host , . body composition analyzer

LF

CR3D

Host , . body composition analyzer

LF

CR!3D

If commands accepted

If settings incorrect

Host , . body composition analyzer

LF

CR4D

Host , . body composition analyzer

LF

CR!4D

If commands accepted

If settings incorrect

Host , . body composition analyzer

LF

CR0.1000D

If commands accepted

Host , . body composition analyzer

LF

CR11D

Host , . body composition analyzer

LF

CR02D

Host , . body composition analyzer

LF

CR971003D

Host , . body composition analyzer

LF

CR434D

Host , . body composition analyzer

LF

CR816D

Host , if data settings incorrect . body composition analyzer

If settings incorrect

Ex: 18%

Host . /body composition analyzer

LF

CR816D

Host , . body composition analyzer

LF

CR6D

Host , . body composition analyzer

LF

CR!6D

If commands accepted

If settings incorrect

Set target BF

8

33

Switch on body composition analyzer.

1

Choose the units of measurement.

2

First, switch on the body composition analyzer.



Check that the unit is in Remote mode.

Also check that the unit is connected properly to the computer.

Set tare weight

3

The tare weight need not be set if not required. It will then be treated as 0.

Ex: 1kg tare weight

Host . /body composition analyzer

LF

CR0.1000D

Ex: cm/kg



Units of measurement cannot be set if tare weight and height have been set. The default setting is cm/kg.

Host . /body composition analyzer

LF

CR0U

Host , . body composition analyzer

LF

CR0D

Host , . body composition analyzer

LF

CR!D

If commands received

Host , . body composition analyzer

LF

CR0U

If settings incorrect

Host , . body composition analyzer

LF

CR!U

If commands received

If settings incorrect

Set gender

4

Ex: male

Host . /body composition analyzer

LF

CR11D

Host , . body composition analyzer

LF

CR1D

Host , . body composition analyzer

LF

CR!1D

If commands accepted

If settings incorrect

*If commands sent are unclear Host

,

commands returned

LF

CR!

 Example of Use

The body composition analyzer is used remotely as follows.

32

Reset settings

Host . / body composition analyzer

If commands accepted : Host , . body composition analyzer

If settings incorrect : Host , . body composition analyzer

LF

CR!

LFCRCHR$(01FH)

LFCRCHR$(01FH)

 Resetting

Cancel measurement

Host . / body composition analyzer

If commands accepted : Host , . body composition analyzer

If settings incorrect : Host , . body composition analyzer

LF

CR!

LFCRCHR$(01EH)

LFCRCHR$(01EH)

 Cancel

35

Host . /body composition analyzer

LF

CR1G

Host , . body composition analyzer

LF

CR1G

Host , . body composition analyzer

LF

CR00E

If commands accepted

If settings incorrect

Start measurement

10

Readings will be outputted when measurement is finished.

Host ,

If concluded normally

Host ,

error . body composition analyzer

If an error occurs

Commands are not accepted while measuring is in progress. If an error occurs, the body composition analyzer will transmit an error code to the host.

Host ,

error code . body composition analyzer

During measurement

11

Measurement finished

12

After measurement has finished, all necessary items of data and tare weight are cleared, and the unit waits for further commands.

. body composition analyzer

” 21/ 09/ 02 ” , ” 19:29” ,0,1,

34 ,

00179 ,

Date Time

Height

Age

073 . 3 13 . 1 009.6 063

551 212 214 292

309

.7

046 . 6

Weight

Fat mass

Fat free mass

Body water mass

Body fat percentage

011.5

Fat free mass

001 . 1

Fat mass

08 . 9

Body fat percentage

Right leg

0 23.9 07294

BMI

Whole body impedance

Right leg impedance Left leg impedance

Right arm impedance

Left arm impedance

BMR

010 . 9

Predicted muscle mass

011 . 0

Fat free mass

001.2

Fat mass

10 . 1

Body fat percentage

Left leg

010 . 4

Predicted muscle mass

CR LF

Terminator

003 . 6

Fat free mass

000 . 6

Fat mass

14 . 0

Body fat percentage

Right arm

003 . 4

Predicted muscle mass

003 . 5

Fat free mass

000.6

Fat mass

15 . 4

Body fat percentage

Left arm

003 . 3

Predicted muscle mass

034 . 1

Fat free mass

006 . 0

Fat mass

15.0

Body fat percentage

Trunk

032 . 8

Predicted muscle mass

,

,,

,,,,

,,,,

,,,,

,,,,

,,,,

,,,

,,,,

,

Body type

Gender

34

36

Reliability of body composition measurements with an 8-electrode BIA

Introduction

This device calculates body fat percentage, fat mass, fat free mass, and predicted muscle mass on the basis of
data obtained by Dual Energy X-ray Absorptiometry (DXA) using Bioelectrical Impedance Analysis (BIA).
One of two settings must be selected when taking measurements:
1

Standard (for persons 7 ~ 99 years of age)

2

Athlete (sportsmen/women who exercise considerably more than non-athletes)
Making a distinction by body type in the measurement mode produces more reliable body composition
measurements for athletes, whose body compositions differ from those of average persons.

BIA is a means of measuring body composition – fat mass, predicted muscle mass, etc. – by measuring
bioelectrical impedance in the body. Fat within the body allows almost no electricity to pass through, while
electricity passes rather easily through water, much of which is found in muscles. The degree of difficulty
with which electricity passes through a substance is known as the electrical resistance, and the percentage of
fat and other body constituents can be inferred from measurements of this resistance.
The Tanita Body Composition Analyzer measures body composition using a constant current source with a high frequency

current (50kHz, 500μA). The 8 electrodes are positioned so that electric current is supplied from the electrodes on the tips of

the toes of both feet and the fingertips of both hands, and voltage is measured on the heel of both feet and the thenar side of
both hands. The current flows into the upper limbs or lower limbs, depending on the body part(s) to be measured.

 Principles of body composition measurement via 8-electrode BIA

 Body impedance measurement methods

In the conventional 4-electrode method, current is supplied from the electrodes at the tips of the toes on both feet, with the voltage
measured on the heel. This current flows from one lower limb through the lower abdomen and then into the other lower limb, and the
bioelectrical impedance (hereinafter, “impedance,”) thus measured is the impedance between the two feet. In the newly developed 8­electrode method, however, current is supplied from the tips of the toes of both feet and the fingertips of both hands, and the voltage is
measured on the heel of both feet and the thenar side of both hands. This method allows five different impedance measurements to be
made – whole body, right leg, left leg, right arm, and left arm – by switching the part of the body in which the current is flowing and
the location where the voltage is measured. When measuring impedance in the right leg, for instance, the current flows between the
right hand and foot, and the voltage between both feet is measured.
For reference, the impedance measurement methods for the respective body parts are shown in the diagram below.

Technical Notes

Whole body Left legRight leg Right arm Left arm

Current

Voltage

Impedance measurement methods for the respective body parts

37

In deriving the body fat percentage, fat mass, and fat free mass for the whole body, the Body Composition
Analyzer uses data acquired by DXA* from both Japanese and Western subjects as well as a regression
formula derived through repeated regression analysis using height, weight, age, and impedance between
right hand and foot as variables. Measurements of body fat percentage, fat free mass, fat mass, and
predicted muscle mass for specific body parts also use a regression formula for each body part derived from
repeated regression analysis using height, weight, age, and impedance for individual body parts (right arm,
left arm, right leg, left leg, trunk) as variables, based on data acquired through DXA.
A high degree of correlation has been found to exist between the figures for body fat percentage, fat mass,
and fat free mass for individual parts and for the entire body calculated with this predictive formula and the
figures obtained by DXA, and the results are thus highly reproducible.
Body composition measurements attained by the 8-electrode method are therefore extremely reliable.

Measurement of body composition using DXA

DXA was originally designed to measure bone mineral content, but in the full-body scan mode the body
fat percentage, fat mass, and fat free mass of individual body parts (arms, legs, trunk) can also be
measured. The image below shows one example of body composition measurement results obtained by
DXA.

Body composition measurement results obtained by DXA (Lunar Co., Ltd; DPX-L)

 Reliability of body composition analysis via 8-electrode BIA

39

Intra-day changes are thought to occur in unique cycles
arising from differences in the rhythm of individual daily
routines, occupations, and day-to-day activities.
Consequently, to obtain consistent measurement figures it is
recommended that measurements be taken under the
following conditions:

1) Measuring three hours or more after waking up, with
normal day-to-day activities carried on during this time
(simply sitting or traveling by car will keep impedance
high)

2) Measuring three hours or more after last eating

(impedance tends to fall for 2 to 3 hours after a meal)

3) Measuring twelve or more hours after vigorous exercise
(changes in impedance vary, depending on the type and
intensity of the exercise done)

4) Urinating before the measurement

5) Measuring as far as possible at the same time every day
in the case of repeated measurements (more dependable
measurements can be obtained if body weight and
impedance are both measured at fixed times)

Complying with the conditions above should result in very
consistent measurements.
When developing this device, the following six conditions
were established in deriving the regression formula:

1) No alcohol less than 12 hours prior to measurement

2)

No vigorous exercise less than 12 hours prior to measurement

3) No excess food and drink on the day before measurement

4)

No food and drink less than 3 hours prior to measurement

5) Urination immediately before measurement

6) No measurements during menstrual period (women)

-60

60

40

20

Intra-day fluctuations (Impedance value)

Time

Between hand and foot

Between both hands

Between both legs

0

-20

-40

6

10

14

18

22

8

12

16

20

Ω

Rising

After

breakfast

Before breakfast

After lunch

Before lunch

Before supper

After

supper

Before bathing

After bathing

Sleeping

Intra-day fluctuations( %FAT)

％

-3.0

3.0

2.0

1.0

Time

0.0

-1.0

-2.0

6

10

14

18

22

8

12

16

20

Between hand and foot

Between both hands

Between both legs

Rising

After

breakfast

Before breakfast

After
lunch

Before lunch

Before

supper

After supper

Before bathing

After bathing

Sleeping

6

-1.0

-1.5

1.5

1.0

0.5

0.0

-0.5

10

14

18

22

8

12

16

20

Intra-day fluctuations (Weight)

Time

kg

Rising

After breakfast

Before breakfast

After lunch

Before lunch

Before supper

After supper

Before bathing

After bathing

Sleeping

BIA measures impedance and calculates body composition on the basis of this impedance. It is known,
however, that impedance can vary due to changes in the quantity and distribution of body water, which
accounts for approximately 60% of body weight, as well as changes in body temperature. Therefore, when
measurements are being taken for research purposes or on a daily basis, uniform measurement conditions
must be ensured.

Consideration should be given to two types of changes in impedance: inter-day changes and intra-day
fluctuation (cyclic changes within a single day). In the 8-electrode method, full body measurements use the
impedance between the arms and legs, while measurements for specific body parts use the impedance of
those particular body parts.
The reasons for changes in impedance are different for the upper limbs and the lower limbs. Given that the
impedance of the trunk is extremely low (a mere 5-10% of the impedance between hands and feet), changes
involving the trunk can be almost wholly ignored when measuring the impedance between hands and feet,
and the changes for the upper and lower limbs are synthesized.
When studying intra-day and inter-day changes with the 8-electrode method, it is thus necessary to
determine the respective changes for the upper and lower limbs.

1) Intra-day fluctuations (cyclic activity within a single day)

Peripheral impedance ordinarily rises during sleep and falls during activity. This is believed to occur
because extracellular fluid, typified by the blood, moves to the trunk during sleep, reducing the
extracellular fluid in peripheral areas and thus increasing impedance, and because the extracellular fluid
returns to peripheral areas during activity, causing a drop in impedance.
Intra-day activities during this cycle cause changes in body water volume and distribution due to the
consumption of food and drink as well as exercise.
The charts on page 33 illustrate one example of intra-day activities. The changes in weight, impedance, and
body fat percentage are shown on the respective vertical axes, while the measurement times are shown on
the horizontal axes (plotted points indicate the variation from the average change).
Increases in body weight occurred following the consumption of food or drink, and a sharp decrease was
seen between 20:00 and 22:00 because of a bath.
The impedance between the hands and feet, as mentioned earlier, synthesizes the changes in impedance of
the upper limbs and the lower limbs.
During the two or three hours of digestion and absorption that followed breakfast and lunch, a decrease occurred
in the impedance of both the upper and lower limbs, but the degree of change was larger in the lower limbs than
in the upper limbs. This is because the impedance of the upper limbs temporarily increased due to the impact of
specific dynamic action (SDA) from the meals but then turned downward as the body fluid mass increased. No
such increase or decrease in impedance due to SDA was seen, though, in the lower limbs. After supper, the lower
level of activity caused an increase due to lessened extracellular fluid in peripheral areas at the same time that
upper and lower limb impedance fell due to digestion and absorption; as a result no clear trend could be seen.
Among the particularly large changes that occurred were decreases in impedance while taking baths and
subsequent increases, increases and decreases attributable to exercise, and decreases after tasks such as
carrying heavy objects that require use of the upper limbs. In the course of a single day, the largest intra-day
change in the lower limbs was the decrease in impedance due to the flow of blood to the lower limbs (blood
congestion). No clear trend was noted in impedance in the upper limbs over the course of a single day, but
extremely large changes did occur as a result of certain activities in the daily routine.

 Causes of errors in impedance measurements

38

2) Inter-day changes

The diagrams below offer examples of actual measurements made of inter-day changes. A study was done
to determine the degree of change in the impedance between the feet during dehydration; the first two days
represent a normal daily routine, while in the latter two days a state of dehydration was induced using a
sauna.

No significant inter-day change was measured in body
weight, impedance between the feet, or body fat percentage
during the normal daily routine. During the dehydrated
state, however, a drop in body weight of 1kg was noted,
with the impedance between the feet rising approximately
15Ω on the first day of dehydration and 30-35Ω on the
second day. As a result, body fat percentage was up by
around 1% on the first day of dehydration and by 1.5-2% on
the second day.
As mentioned earlier, impedance increases when body
weight is reduced (such as by dehydration), and decreases
when body weight is increased through excess
consumption of food and drink. The inter-day change in
impedance is thus inversely proportional to the change in
body weight.
These inter-day changes stem from such causes as:

1) Temporary increases in body weight (total body water)
through overeating and overdrinking

2) Dehydration due to heavy sweating during vigorous
exercise

3) Dehydration due to alcohol consumption or the use of
diuretics

4) Dehydration due to heavy sweating during saunas, etc.

Accordingly, it is recommended that instructions be
provided to the subject to help eliminate these causes when
accurate measurements are needed.

kg

Time

Intra-day fluctuations (Weight)

61

60.5

60

59.5

59

58.5

58

10：00 18：0016：0014：0012：00

＋5/13（Monday） ◆5/14（Tuesday） ▲5/15（Wednesday） ×5/16（Thursday）

10：00 18：0016：0014：0012：00

Ω

Time

Intra-day fluctuations (Impedance value)

420
410
400
390
380
370
360
350

340

＋5/13（Monday） ◆5/14（Tuesday） ▲5/15（Wednesday） ×5/16（Thursday）

％

Time

Intra-day fluctuations ( %FAT)

22

21

20

19

18

17

10：00 18：0016：0014：0012：00

＋5/13（Monday） ◆5/14（Tuesday） ▲5/15（Wednesday） ×5/16（Thursday）

Inter-day changes in body fat percentage and

impedance measured by BIA between the feet

during normal daily routine and during

dehydration

40

THE APPLICABILITY OF THE BMR REGRESSION FORMULA AND
ITS DIFFERENCES WITH THE OLD FORMULA

The New Regression Formula for Basal Metabolic Rate (BMR)

It has long been said among medical and nutritional specialists that "The Basal Metabolic Rate (BMR) is
more determined by the Fat Free Mass (FFM) than by the body weight" (Persons of a given body weight
with a higher FFM will have a higher BMR), and that from the aspect of evaluating the body composition,
should be estimated from the FFM. In addition, in cases of simple estimation formulae which can calculate
from the height, weight and age, without evaluating the body composition, there was a problem with
excessively high evaluations being given to obese persons with large body weight, and conversely
excessively small BMR evaluations given to muscular athletes, though these are not as many in number.
Currently, the BMR estimation recursion formula developed by Tanita, the manufacturer of body
composition analyzers, based on their research, works by multiple regressive analysis using this FFM, and
has a higher degree of accuracy in the individual differences in body composition. In order to derive the
BMR, resting respiratory metabolism (Resting Energy Expenditure: REE) was measured using a breath gas
analysis device, and this estimation recursion formula was created based on this data.

<Figure 1> The Relationship Between Resting Energy Expenditure (REE) According

to Breath Gas Analysis and Weight, FFM

(Presented at Nutrition Week, Held in San Diego in 2002)

FFMvsREE

3000

2500

2000

1500

1000

500

10 30 50

FFMkg

JPMale

REE(→BMR) kcal/day frombreath

JPFemale USMaleUSFemale

Female

Male

70 90

0

WeightvsREE

3000

2500

2000

1500

1000

500

30 50 70

Weghtkg

JPMale

REE(→BMR) kcal/day frombreath

JPFemale USMaleUSFemale

Female

Male

90 110 130

0

41

43

Product specifications

Output Items

Measurement System

Measurement Frequency

Impedance

Measurement

Weight

Measurement

Input Items

8 polar Bioelectrical Impedance Analysis

50kHz

Measurement Current

500µA

Electrode Material

Pressure Contact Stainless Steel Foot Pads, The Hand Grips are Metal-Plated to ABS Resin.

Measurement Style

Whole body, Right leg, Left leg, Right arm and Left arm

Measurement Range

150 ~ 1200Ω

Measurement System

Maximum

Capacity

Minimum

Graduation

Strain Gauge Load Cell

Accuracy at first calibration

200 kg / 0.1 kg 440 lb / 0.2lb

±0.2kg ±0.4lb

Clothes Weight

0-200 kg / 440lb 0.1 kg increments / 0.2 lb increments

Gender

Male / Female

Body Type

Standard / Athletic

Age

7~99 years old /1year increments

Height

Display

Print-out

Display

90 - 249 cm / 3 ft - 7 ft 11.5 in 1 cm increments / 0.5 in increments

Target Body Fat %

4~55%

Weight

0 - 200 kg / 440 lb 0.1 kg increments / 0.2 lb increments

Target Body Fat %

4~55%

Gender

Male / Female

Body Type

Standard / Athletic

Age

7 - 99 years old / 1 year increments

Height

90 - 249 cm / 3 ft - 7 ft 11.5 in 1 cm increments / 0.5 in increments

FAT%

1 - 75% / 0.1% increments

Body Type

Standard / Athletic

Gender

Male / Female

Age

7 - 99 years old / 1 year increments

Height

90 - 249 cm / 3 ft - 7 ft 11.5 in 1 cm increments / 0.5 in increments

Weight

2 - 200 kg / 4 – 440 lb 0.1 kg increments / 0.2 lb increments

BMI

0.1 increments

BMR

1 kJ increments / 1 kcal increments

Impedance *1

150 ~ 1200 Ω / 1Ω increments

FAT% *2

1 - 75% / 0.1% increments

Fat Mass *2

0.1 kg increments / 0.2 lb increments

FFM *2

0.1 kg increments / 0.2 lb increments

TBW

0.1 kg increments / 0.2 lb increments

Predicted Weight

0.1 kg increments / 0.2 lb increments

Predicted fat mass

0.1 kg increments / 0.2 lb increments

FAT TO LOSE/GAIN

0.1 kg increments / 0.2 lb increments

Predicted muscle Mass *2

0.1 kg increments / 0.2 lb increments

Others

Desirable Range for FAT% and FM

3 Rows, 5 Digits LCD

Output Data Interface

RS-232C (D-sub 9 pins male Connector)

Temperature Range of Usage

0ºC/35ºC

Power Consumption

Relative Humidity

17.5 W

BC-418

Power source

AC adaptor (included) Center Minus MODEL SA25-0535U CLASS 2

Input Voltage: 100-240 VAC 50/60 Hz 550mA Output Voltage: 5 VDC ± 0.3 V

Rated Current: 3.5 A No Load Input Voltage: 5 VDC ± 0.3 V

30% / 80% (without condensation)

Weight of Equipment

12kg

Size

Accuracy at first calibration

12Ω

Weighing Platform

377 X 343 X 83mm

830mm

Height

/

*1 This item displays Whole Body, Right Leg, Left Leg, Right Arm and Left Arm.
*2 This item displays Right Leg, Left Leg, Right Arm, Left Arm and Trunk.

The current BMR retrogression formula is a formula which acts on the principle of using the FFM value
from the results of body composition measurement according to the BIA, A good relationship is shown in
the BMR value based on actual breath analysis REE or R=0.9 (p<0.0001). These results were presented at the
First Annual Nutrition Week (American College of Nutrition, American Society for Clinical Nutrition,
American Society for Parenteral and Enteral Nutrition, North American Association for the Study of
Obesity) held in 2002 in San Diego.

NOTE: This model has been calibrated for those between ages of 18-84.

Those individuals outside of this age range may not be obtain accurate readings.

As shown in Figure 1: the REE (BMR) has a stronger relationship to the FFM than to body weight, and a
difference is visible between males and females in the distribution trends. We see that in principle that we
should calculate from the FFM rather than by the old formula centered on the relationship with weight.

<Fig: 2> Comparison of BMR Values from the TANITA Multiple regression model and Breath Analysis

(Presented at Nutrition Week Held in San Diego in 2002)

3000

y=x+9E– 11
R

2

=0.808
R=0.900
SEE=131.4
p<0.0001

2500

2000

1500

1000

500

0 1000 2000

TANITABMRkcal/day

(fromTANITAmultipleregressionanalysismodel)

REE(→BMR) kcal/day frombreath

3000

0

JPMale JPFemale USMaleUSFemale

42

BC4187001(3)

This device features radio interference suppression in compliance with valid EC Regulation 89/336/EEC.

14-2,1-chome,Maeno-cho,Itabashi-ku
Tokyo,Japan
Tel:[phone] Fax:[phone]

Dresdener Strasse 25
D-71065 Sindelfingen,
Germany
Tel : [phone]
Fax : [phone]

Unit 301-303 3/F Wing On Plaza,
62 Mody Road, Tsimshatsui East,
Kowloon, Hong Kong
Tel : [phone]
Fax : [phone]

2625 South Clearbrook Drive
Arlington Heights, Illinois 60005 U.S.A.
Toll Free : [phone]
Tel : [phone]
Fax : [phone]
http : //www.tanita.com

Villa Labrouste
68 Boulevard Bourdon,
92200 Neuilly-Sur-Seine,
France

Tel

: 01 55 24 99 99

Fax : [phone]

The Barn, Philpots Close,
Yiewsley, West Drayton,
Middlesex, UB7 7RY,
United Kingdom
Tel

: [phone]

Fax : [phone]