Gentek 3980421 User Manual

1.34 Mb

Chapter 5: Using Your Filtered Enclosure and Appropriate Application

IDLH (Immediately Dangerous to Life and Health). An atmosphere that poses an immediate hazard to life or produces immediate irreversible health effects. IDLH concentrations should not be approached in the enclosure.

Appropriate Chemicals for Odor Control Carbon Filters

Below is a general set of rules to determine appropriateness of chemical usage.

Selected organic chemicals considered to be ! occupational carcinogens by NIOSH can be used

in the filtered enclosure with carbon filters under rigid restrictions. See separate discussion on carcinogens for special instructions.

Organics must have time weighted exposure limits (TWA) of 1

PPM or greater.

Chemicals must have a detectable odor at concentrations below the

TWA for the chemical.

Chemicals must be designated by NIOSH guidelines as acceptable for use with chemical cartridge-typerespirators (the exception is formaldehyde and ammonia/amines, which used impregnated carbon). Chemicals not listed by NIOSH in the Pocket Guide must be approved by Labconco Product Specialist (or Engineering).

Inlet concentration must never exceed the IDLH (Immediately

Dangerous to Life and Health) concentrations.

Chemicals having a recommendation by NIOSH of at least “Escape GMFOV” (Gas Mask Full-FaceRespirator).

When evaporating a mixture of chemicals, the chemical having the lowest TWA will be used to determine if the mixture meets the guidelines.

Call a Labconco Product Specialist at 1-800-821-5525for assistance in chemical appropriateness.


Chapter 5: Using Your Filtered Enclosure and Appropriate Application

Hazardous Misapplications for Odor Control Carbon Filters with Volatile Chemicals

There is one scenario where the accessory carbon filter misapplication would be a part of a hazardous condition. If the user continues to operate the enclosure with any of the following conditions present a potentially hazardous condition will exist:

1.The inlet concentration of vapors is greater than the TWA.

2.The carbon filter becomes saturated.

3.The ventilation of the room is insufficient to dilute the exhaust of the enclosure to below the TWA for the


When the inlet concentration is greater than the TWA, extra measures must be taken to monitor the filter and number of room air exchanges.

Chemical Carcinogen Use with Odor Control Carbon Filters

Selected carcinogens may be used safely with Odor Control carbon filters under the following restrictions.

The use of a vented fume hood or ventilated

!enclosure with ducting to the outside is always the preferred method when working with carcinogens. The Odor Control carbon filters should only be used, as a last resort when venting to the outside is not an option.

The potential carcinogens are listed in the NIOSH Pocket Guide to Chemical Hazards as “Ca.” Each potential carcinogen must have a TWA of 1 or greater; have minimum respirator recommendation of Escape GMFOV, and an odor threshold significantly lower than the TWA for the chemical.

The inlet concentration or the evaporation rate of the chemical must never exceed the TWA for the chemical.


Chapter 5: Using Your Filtered Enclosure and Appropriate Application

Consult a Labconco Technical Specialist for estimated saturation life. See Chapter 6 for an example of estimating saturation life. Another source is the Labconco chemical guide for carbon filtered enclosures.

Prohibited Acid Use

The Purifier HEPA and Purifier Class I filtered enclosures motorized impeller cannot be exposed to acids. Where applications require the use of acids, a separate ventilated enclosure or vented fume hood should be used with a remote blower ducted to the outside.

No exceptions are permitted, as the impeller life span will be limited with acid use.





Monitoring airflow and changing the filters is the primary maintenance required. Decontamination may be required and is reviewed in Chapter 6. Certification and recertification is reviewed in Chapter 6.

Review this chapter on maintenance for the following:

1.Routine Maintenance.


3.Determination of when to replace the HEPA filters.

4.How to install a new HEPA filter.

5.HEPA filter leak test.

6.Speed control adjustment and setting the inflow face velocity.

7.Operating and calibrating the airflow monitors.

8.Determination of when to replace Odor Control carbon filters and how to replace.

9.Calculating Odor Control carbon filter life.

10.Initial certification.


12.Fluorescent light replacement.

13.UV light replacement on Purifier Class I.

14.Motorized impeller replacement.

15.Speed control replacement.


Chapter 6: Maintaining Your Filtered Enclosure




Routine Maintenance Schedule


Wipe down the interior surfaces of the enclosure with a disinfectant or cleaner, depending upon the usage of the unit and allow to dry.

Using a damp cloth, clean the exterior surfaces of the enclosure, particularly the front and top to remove any accumulated dust.

Operate the exhaust system, noting the airflow velocity through the enclosure using a source of visible smoke. Airflow monitors are recommended for constant monitoring.

Monthly (or more often as required)

Determine the actual face velocity through the sash opening of the enclosure where the average reading should be at the specified velocity. (Use calibrated thermal anemometer or other approved apparatus). Airflow alarms are recommended for constant monitoring.

The enclosure rear baffle should be checked for any blockage to ensure that the enclosure is maintaining proper airflow.

All weekly activities.

Check face velocity. Increase speed control or change HEPA filter when face velocity of the enclosure drops below the recommended speed for your facility or if the airflow alarm monitor alerts you. Airflow monitors are recommended.

While the enclosure is filled with the contaminant, test filter condition on Odor Control carbon filters using the appropriate gas detector tube at intervals of 20% of the total estimated time. The exception to the 20% recommendation is formaldehyde or any carcinogen or suspected carcinogen. These hazardous chemicals must be checked at least every 10% of the total estimated time. Gas detector tubes for the specific chemicals that are being used in the enclosure can be obtained from your laboratory supply dealer.

Replace Odor Control carbon filters when chemical breakthrough is indicated by odor, time, detector tube, or for some chemicals, analytical instrumentation. See “Replacing Odor Control Carbon Filters” section of this manual in Chapter 6.


Chapter 6: Maintaining Your Filtered Enclosure


Replace the fluorescent lamps. Replace UV lamps if equipped.

Have the enclosure validated by a qualified certification technician. See Certification and Recertification in Chapter 6.

All monthly activities.


When used in conjunction with biohazards, the Purifier Class I Enclosure and Purifier HEPA Filtered Enclosure should be decontaminated with formaldehyde gas before:

maintenance work in contaminated areas

HEPA filter changes

moving the cabinet to a new location

changing research programs

after a gross spill of biohazardous material

The procedures for performing a gaseous decontamination are thoroughly outlined in the U.S. Department of Health, Education and Welfare booklet entitled Formaldehyde Decontamination of Laminar Flow Biological Safety Cabinets, available from NIH, Division of Safety, Bethesda, MD 20892, call301-496-2801,or from Labconco Corporation.

Determination of when to Replace

HEPA Filters

The HEPA filters in the filtered enclosures gradually accumulate airborne particulate matter and powders from the enclosure and room. The rate of accumulation will depend upon the cleanliness of the room air, the amount of time the enclosure is operating, and the nature of work being done in the enclosure. In typical installations and usage, the HEPA filters will last two to five years before requiring replacement. Replace HEPA filters when face velocity drops below the recommended 75-105fpm velocity, and the speed control is adjusted to full speed. Replace HEPA filters if it fails the HEPA Filter Leak Test in Chapter 6.


Chapter 6: Maintaining Your Filtered Enclosure

How to Install a New HEPA Filter

NOTE: The enclosure must be properly decontaminated before servicing the HEPA filter. Only a qualified certifier should service the HEPA filter. After the HEPA filter is replaced, the enclosure MUST be certified. See Figure 6- 1.

1.Unplug the enclosure.

2.Remove the front panel by loosening the two screws that secure it, and then remove the filter access cover.

3.Using a 9/16" deep socket, loosen the filter clamp bolts located on top. Refer to Figures 4-1and4-2.

4.With the clamp bolts loosened, the HEPA filter-clampingframe should be clear of filter. Carefully pull the filter straight out of the enclosure and discard properly.

5.With the filter removed, inspect the clamping frame and the frame of the cabinet for damage.

6.Cover the surface of the new HEPA filter gasket with a light coating of silicone grease, if desired.

7.Install the new HEPA filter by pushing it straight into the cabinet, ensuring that it is correctly oriented with the gasket facing up on the exhaust side of the enclosure. The filter gasket is surrounded by a negative pressure plenum and the gasket will not leak. Be sure the filter fits properly.

CAUTION: The filter clamp bolts should only be tightened enough to ensure a proper seal at maximum tightness. The filter gasket should be compressed 50% or less.

8.Tighten the clamp bolts uniformly until the filter gasket is properly compressed against the frame. Inspect the seal thoroughly before proceeding.

9.Reinstall the filter access cover and the front panel.

10.Plug the enclosure in and have it recertified before use.


Chapter 6: Maintaining Your Filtered Enclosure

Figure 6-1

HEPA Filter Changing Diagram & Filter Leak Test Diagram


Chapter 6: Maintaining Your Filtered Enclosure

HEPA Filter Leak Test

HEPA Purpose

After installing the new HEPA filter, the HEPA filter should be leak checked. This test is performed to determine the integrity of the HEPA filter, the filter housing, and the filter mounting frames. Leak testing is to be done by a qualified technician with calibrated equipment. Remove the top perforated exhaust cover by using a Phillips screwdriver to unfasten the (2) screws used to secure (2) clips. See Figure 6-1.The filter passes the leak test at .01% or better. Reference Leak Testing and Photometer scanning from the Institute of Environmental Services(IES-RP-CC001.3)


1.An aerosol photometer ATI model 2D, 2E, 2G or equivalent. Air Techniques Hamilton Associates inc. 11403 Cron Ridge Dr. Owings Mills, MD 21117

2.One aerosol generator of the Laskin nozzle(s) type. An aerosol of mineral oil or suitable liquid shall be created by flowing air through it. The compressed air supplied to the generator should be adjusted to a pressure of 10± 1 psig. during operation. Air Techniques Inc. Model TDA-4A or equal. One nozzle at 10 psig is (67.5 cfm x 100ug/l)/(Vol. of air), For the 2' at 90 fpm or 130 cfm, one nozzle @10 psig is 13,500/130 cfm = 52 ug/l. For the 3' at 90 fpm or 200 cfm, one nozzle @ 10 psig is 34 ug/l. For the 4' at 90 fpm or 265 cfm, one nozzle at 10 psig is 26 ug/l.

3.Mineral oil (Catalog #1491400).

4.Sampling Nozzle, Rectangular 1/2" x 3-1/4", Air Techniques, Inc.


For the ATI 2G Photometer

1.Turn on the photometer and allow it to operate for a minimum of 5 minutes. Leave the valve in the “CLEAR” setting.

2.Press the “ENTER” keypad. Press the “REF” keypad.

The display will display “P1” for approximately 1 second, and then display a numerical value.

3.The display will display “P1” for approximately 1 second, and then display a numerical value.


Chapter 6: Maintaining Your Filtered Enclosure

4.Using the “^” or “ν” keypads, respectively, increase or decrease the numerical value until it equals 52 (2'), 34 (3'). 26 (4') for the enclosure at 90 fpm inflow velocity.

5.Press the “ENTER” Keypad. The photometer will scan for 15 seconds, and then the “0” keypad will flash. Press the “Enter” keypad. The unit will scan for 5 seconds, the display will read “0000,” and the unit will sound a confirming tone.

6.Set the valve to “DOWNSTREAM.” Place the palm of your hand over the sampling port of the pistol. There should be a strong vacuum at this port. If the vacuum is weak, contact Air Techniques Hamilton Associates.

7.Turn the enclosure on and let it operate for a minimum of 5 minutes.

8.If necessary, adjust the speed control of the enclosure to maintain the following airflows at 90 fpm; 2' (130cfm), 3' (200 cfm, 4' (265 cfm.)

9.Position the aerosol generator discharge in the intake of the baffle inside the enclosure.

10.Start the aerosol generator (Pressure to be +/- 1 PSIG). Ensure that one Laskin nozzle is in the “open” position.

11.Allow the generator to operate for a minimum of 15 seconds. For all integral motorized impeller models, scan the downstream exhaust side of the HEPA filter by passing the sampling nozzle of the gun in slightly overlapping strokes over the entire surface the filter, with the sampling port not more than 1 inch from the surface of the filter media. Scan the entire periphery of the filter and the gasket between the filter frame and the enclosure frame. Scanning shall be done at a traverse rate of not more than 2 inches per second.

NOTE: For the Purifier Enclosures ducted to the outside, place the sampling nozzle in the center of the remote blower exhaust.


Aerosol penetration shall not exceed 0.01 percent measured by the photometer.