EHS-080 Industrial Hygiene Sampling for Airborne Contaminants

5.1 General Guidance

5.1.1 Obtaining Sampling Equipment

Sampling supplies such as pumps, calibrators and other sampling accessories can be obtained on a rental basis.

5.1.2 Obtaining Sampling Supplies

Questions regarding the sampling of drug substance or industrial chemical and information regarding obtaining sampling supplies may be found on the local EHS procedure.

5.1.3 Collection of Samples

When placing the sample pump on an individual for personal monitoring or when taking an area sample, the sampling media / holder (filter cassette or sorbent tube) must face downward to avoid collection of settling contaminants from the air. (Impingers should be placed in a manner to prevent spillage of the solution.)

For personal samples, the sampling media / holder should be placed near the individual’s breathing zone, within a 0.3 meter radius, such as attached to the shirt collar.

Generally, if the person is right-handed, attach the sample media to the left side of the lapel.  If left-handed, attach to the right lapel.

Unless validating a respirator protection factor, the sample media is generally worn on the outside of any protective clothing or respiratory protection.

Tubing should extend from the sample media, over or under the shoulder, down the back and to the pump attached to the belt.

If permitted, tape the slack tubing to the clothing to minimize possible interference of the tubing with work activities.

Ensure the individual is comfortable and able to easily move both arms without dislodging the pump, tubing or sampling media.

For area samples, fix the location of the sampling train to within 1m of the operation using a tripod.

Where possible remain in the work area for the duration of the sampling period recording observations such as:

The operation being carried out

Product dosage strength

Quantities of materials being handled

Containers being used for charging and unloading equipment

Transition pieces being used at the charging and unloading points

Local exhaust ventilation at the charging and unloading points and

Personal protective equipment being used.

5.1.4 Number of Samples to Collect

If possible, at least three samples should be collected at the workplace. These can be personal, area or a combination of personal / area samples; full shift or unit operation depending on sampling strategy.

5.1.5 Sampling for Solids

When sampling for a full shift, change the filter cassettes periodically based on the expected airborne concentration of the contaminant. For task or unit operations use one filter cassette for the duration of each task.

5.1.6 Sampling Gases and Vapours

When sampling for a full shift, change the sample media periodically based on the expected airborne concentration of the contaminant. Generally, sorbent tubes and badges should be changed regularly (at least twice over the course of an 8 hour day) to prevent breakthrough of the analyte(s).  Breakthrough is assumed to occur when >25% of an analyte is found on the back section of the tube. Impinger solutions may require more frequent changing of solution.

5.1.7 Sending Samples for Analysis

Details of the current laboratory used for sample analysis is available on site EHS procedure. Samples should be sent by courier, using enough packaging materials to protect the samples.

A completed Industrial Hygiene Sampling Report (Appendix 1) and MSDS for each material sampled should also be submitted to the laboratory.  A small (approximately1g) sample of a recent delivery of each substance should also be included in the shipment to be used as a reference standard.

5.1.8 Communication of Results to Employees and Management

Results should be communicated to the employee who was present at the time of sampling and to their team leader, manager and department head as soon as practical.  It is the Manager’s responsibility to communicate the results to same exposure groups.  Depending on the nature of the results, Form “Industrial Hygiene Sampling Result – Communication to Site Colleague” (Appendix 2) or Form “Industrial Hygiene Sampling Result – Communication to Site Management” (Appendix 3) should be used to communicate these results.

Note that the communication to management includes scope for recommendations to improve the control of airborne contaminants.

Copies of these results must also be filed with the employee’s medical records.

5.2 Procedure Step

5.2.1 Sampling for Solids Remove the plastic cassette plugs prior to switching on the sampling pump.

Record observations during the operation / activity and record them on Form “Industrial Hygiene Sampling Report” (Appendix 1).

Periodically check the pump to ensure it continues to function properly.

Re-seal filter cassettes with supplied plastic plugs immediately at the conclusion of sampling.

Recheck the pump calibration and note flow rates and sampling times on the observation form.

Place cassettes in a plastic bag and store in a refrigerator (for up to ten days) prior to shipping to the laboratory.

Transport sampling media to the laboratory by courier, with cassettes packaged tightly in an upright position and padded for shipment to the laboratory to minimize shock and damage. See the General Guidance section above (Section 5.1).

5.2.2 Sampling Gases and Vapours

Remove the sealing plugs prior to switching on the sampling pump.

Record observations during the operation / activity and record them on Form “Industrial Hygiene Sampling Report” (Appendix 1).

Periodically check the pump to ensure it continues to function properly.

At the conclusion of sampling:

– Re-seal sorbent tubes with supplied plastic plugs and place in plastic bags.

– Dosimeters:  Remove the diffusion membrane and replace the supplied plastic cover.  Make sure all of the plugs are in place to snap on the cover.  Place the dosimeter in its original container for shipment to the laboratory.

– Impingers: Redilute the impinger to the initial volume, if necessary.  Transfer this solution to scintillation vials with polyseal cone liners for shipment to the laboratory.

Recheck the pump calibration and note flow rates and sampling times on the observation form.

Transport sampling media to the laboratory by courier.  See the General Guidance section above (Section 5.1).