NYC-WTC_000186588

NYC 9/11 Public Portal Document

Liberty Mutual. Industrial Hygiene Measurement Results Key to Air Sample Terminology

The following explanations should help in reading the data chart.

1. Sample ID - Is a unique sample identification.

2. Sample Zone - Refers to the contractor the employee indicated that they were working for.

3. Job Description - Job description of the person on whom the sample was collected.

4. Begin Date and End Date - The date(s) and times on which the sample was collected.

5. Worker - This usually contains the name of the person on whom the sample was collected, but can be an indication of the area in which a sample was collected on an area sample..

6. Respirator - If noted by the technician conducting the air sampling, an indication of whether or not the individual wearing the air sampler was wearing a respirator at least during the times when the sampling device was put on and removed.

7. .Analyte - This is the suspected contaminant substance that was sampled. The sampling and analysis methods are specific to this substance.

8. Results - This is the airborne concentration and units of the analyte found on the sample, usually as an estimated full shift time weighted average exposure. This is the number that should be compared to the OSHA or ACGIH limit.

9. OEL - Occupational Exposure Limit; the lower of the OSHA PEL and ACGIH TLV

10. Shift Adjusted OEL - The OEL lowered, when appropriate, to reflect the fact that 12 hour, 7 day a week shifts are frequendy worked. The “Quebec model” as described in the American Industrial Hygiene Association Journal (AIHJ 62:584-594) was the basis of this adjustment.

11. % OEL - The percent of the OEL represented by the sample result. For example, if a sample result is 'A of the OEL, the % OEL would be 50%.

12. % Shift Adjusted OEL - Percent of the shift adjusted OEL represented by a sample.

13. Results Comment - Not always used. May contain comments from the industrial hygienist or analytical lab about results.

CITY_21MC100_002961477

NYC-WTC_000186588