OHST Industrial Hygiene & Exposure Assessment 2

Question 1

What type of air sampling is used to measure contaminant concentrations specifically in a worker's breathing zone?

Accepted Answer

Personal sampling

Answer

Personal sampling places the sampling device in the worker's breathing zone so it travels with the worker, accurately capturing actual individual exposure.

Question 2

A 'grab sample' in air monitoring is best described as:

Accepted Answer

A sample collected over a short, defined time period

Answer

A grab sample captures air quality at a specific point in time over a brief collection period, providing a snapshot of instantaneous conditions.

Question 3

Which sampling media is most commonly used to collect organic vapors for subsequent laboratory analysis?

Accepted Answer

Activated charcoal tube

Answer

Activated charcoal tubes adsorb organic vapors efficiently; the sample is then desorbed with solvent and analyzed by methods such as GC-MS.

Question 4

Which instrument provides real-time, direct readings of airborne particulate concentrations without laboratory analysis?

Accepted Answer

Direct-reading photometer or optical particle counter

Answer

Direct-reading instruments such as photometers and optical particle counters measure light scatter or attenuation to instantly report airborne particulate concentrations.

Question 5

OSHA's action level for occupational noise exposure, which triggers hearing conservation program requirements, is:

Accepted Answer

85 dBA as an 8-hour TWA

Answer

OSHA's noise action level is 85 dBA as an 8-hour TWA; at or above this level, employers must implement a hearing conservation program.

OHST Exam Practice Test

OHST Exam Practice Test

OHST Industrial Hygiene & Exposure Assessment 2