SKC Limited IOM Multi User Manual

This instruction sheet covers the following sampler models:

• 225-70A I.O.M. sampler in plastic with re-usable plastic cassette

• 225-76A I.O.M. sampler in stainless steel with re-usable stainless steel cassette

• 225-79A I.O.M. sampler in plastic with re-usable stainless steel cassette

Introduction

The I.O.M. sampler* is designed for dust (aerosol) sampling to the
inhalable convention as defined in standard EN481:1993, using
HSE method MDHS 14/3 “General methods for sampling and
gravimetric analysis of respirable and inhalable dust”.

It is highly recommended to obtain and read the document MDHS
14/3, available from the HSE website www.hse.gov.uk, before
carrying out any sampling using the I.O.M. sampler.

Design flow rate is 2.0 l/min, giving a 50% sampling efficiency (cut
point) at 100µm (micron) particle size.

When used with a particle size selective foam insert the I.O.M.
sampler is a validated alternative to the cyclone sampler for dust
sampling to the respirable convention as defined in standard
EN481:1993, using method MDHS 14/3. It is also possible to
carry out multi-dust sampling to determine both the inhalable and
respirable fractions from one sample using the I.O.M. sampler and
foam insert. Refer also to report IR/EXM/99/06 produced by and
available from the Health and Safety Laboratory (UK).

Note that the foam inserts are designed for single use only. A new
foam insert must be used for each sample.

The SKC plastic I.O.M. sampler is manufactured from conductive
plastic which dissipates electrical charges to the surrounding
atmosphere and prevents static interference on the collection of
the dust particles.

The filter is held within a two part, re-usable cassette, suitable for
25mm diameter filters only. The filter and cassette assembly are
weighed as a single unit, reducing the amount of filter handling.
Additionally, any dust that does adhere to the walls of the cassette
inlet is also included in the sample.

The sampler is supplied complete with a cassette sealing cap and
cassette transport clip to prevent contamination of the sample
during transport for laboratory analysis.

For detailed instructions on air sampling in general and use of the
I.O.M. sampler in particular refer to SKC’s 224-G1 Step by Step
Guide to Air Sampling.

www.skcltd.com

I.O.M. Multi-Dust Samplers

Operating Instructions

Figure 1

¹Foam insert only required for respirable
and multi-dust sampling.
²Not required on some models.

A B

Cassette

sealing

cap

Front
plate

O rings

Foam

insert¹

Cassette

front

Filter

Preparing the I.O.M. Sampler for Use

The following instructions give basic details on how to prepare for
dust sampling by gravimetric analysis according to HSE method
MDHS 14/3.

Select two filters from the same box or batch. If carrying out
respirable or multi-dust sampling using foam inserts, also select
two foam inserts from the same box or batch.

One filter (and foam insert) is used whilst calibrating the sample
flow rate and is then discarded, and the second filter (and foam
insert) is pre-weighed to carry out the actual sample.

It is recommended to wear powder free gloves and to use tweezers
when handling filters in order to prevent contamination prior to
taking the sample.

Spring

clip

Sampler

body

Cassette

filter

support

grid

Loading the cassette

Refer to Figure 2 on page 2.

Ensure that the I.O.M. sampler components are cleaned of any
contamination, using a detergent solution. Allow the components
to dry fully before use.

Place the filter to be used for calibration into the cassette support
grid. Fit the cassette front to the support grid, pushing gently until
the two parts of the cassette snap together.

If carrying out respirable or multi-dust sampling, fit one of the two
foam inserts into the inlet of the cassette front, pressing it in evenly
until the front face of the foam insert sits just below the front rim of
the cassette front as shown in Figure 2 on page 2.

O ring²

Outlet

hosetail

Dust cap

A B

Rear view of

front plate detailing

O ring positions

007-05-003 Issue C January 2009

*The I.O.M. sampler is manufactured under license from the Institute of Occupational Medicine, trade mark registered number 2043339E.

Page 1

Figure 2

Foam
insert

Cassette

front

Filter

Cassette

support

grid

Fitting the cassette into the I.O.M. sampler

Ensure that the O ring seals are correctly fitted to the I.O.M.
sampler. Fit the cassette into the sampler body. Screw the sampler
front plate into the sampler body, tightening securely to achieve a
good seal of all of the O rings.

Figure 3

Sampler

inlet

Flow Calibration

Connect the inlet hosetail of the sample pump to the outlet hosetail
of the I.O.M. sampler with a length of flexible tubing. Connect the
flow calibration device (such as a rotameter or Defender primary
calibrator) to the sampler inlet (identified in Figure 3) using an SKC
calibration adaptor (“calidaptor” - part number 391-01). Refer to
the instructions supplied with the calidaptor for further details.

Calibrate the sample flow rate to 2.0 l/min.

Disconnect the I.O.M. sampler from the calibration device. Remove
the cassette from the sampler body, separate the two parts of the
cassette, and remove and discard the calibration filter (and foam
insert).

Pre-Weighing the Filter

Ensure that the parts of the cassette are clean and free of any
contamination.

For inhalable dust sampling -

• Place the remaining filter, to be used for the sample, onto the

cassette support grid. Fit the cassette front to the support
grid, pressing firmly until the two parts snap together.

• Pre-weigh the complete filter and cassette assembly.

For respirable and multi-dust sampling -

• Place the remaining filter, to be used for the sample, onto the

cassette support grid.

• Pre-weigh the filter and support grid only.

• Fit the cassette front to the support grid, pressing firmly until

the two parts snap together. Fit the remaining foam insert, to
be used for the sample, into the inlet of the cassette front,
pressing it in evenly until the front of the foam insert sits just
below the front rim of the cassette front.

• If carrying out multi-dust sampling, pre-weigh the complete

filter, foam and cassette assembly.

Final Checks

Fit the assembled, pre-weighed cassette into the I.O.M. sampler
and secure with the sampler front plate, ensuring a good seal of all
of the O rings.

Quickly re-check the sample flow rate and make any final
adjustments. Switch the sample pump off.

Fit the cassette sealing cap to the sampler to prevent contamination
of the cassette prior to starting the sample.

The I.O.M. sampler is now ready for sampling.

After Sampling

Away from the sample location quickly check the sample flow rate.
Carefully remove the cassette from the sampler body.

Post Weighing the Filter

For inhalable dust sampling -

• Post-weigh the complete filter and cassette assembly.

• The difference between the pre and post weights of the

complete filter and cassette assembly will give the inhalable
sample.

For respirable and multi-dust sampling -

• If carrying out multi-dust sampling, post-weigh the complete

filter, foam and cassette assembly.

• Carefully separate the two parts of the cassette, and post

weigh the cassette support grid and filter only.

• The difference between the pre and post weights of the

complete filter, foam and cassette assembly will give the
inhalable sample.

• The difference between the pre and post weights of the filter

and cassette support grid only will give the respirable sample.

SKC Limited 11 Sunrise Park, Higher Shaftesbury Road, Blandford Forum, Dorset DT11 8ST United Kingdom

007-05-003 Issue C January 2009

T: [phone] F: [phone] E: [e-mail] W: www.skcltd.com

Transportation

If further analysis is required, prepare the sample for transportation
to the laboratory by carefully re-assembling the cassette, fitting the
cassette sealing cap, and fitting the cassette into the transport clip.
This will prevent unwanted ingress or loss of contaminant during
transport.

Figure 4

Foam Insert Ordering Information

Part Number Description

225-772 Respirable foam insert (pack of 10)

225-772-50 Respirable foam insert (pack of 50)

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