AQS Health & Safety Protocols 3 — Questions and Answers
Question 1: An air quality specialist is reviewing stack emission data and finds benzene emissions exceed the NESHAP limit. Benzene is classified as which type of pollutant under the Clean Air Act?
- Criteria pollutant
- Hazardous Air Pollutant (HAP) (Correct answer)
- Greenhouse gas
- Nuisance odor compound
Correct answer: Hazardous Air Pollutant (HAP)
Benzene is listed as a Hazardous Air Pollutant (HAP) under Section 112 of the Clean Air Act, not a criteria pollutant.
Question 2: A worker develops occupational asthma after repeated low-level exposures to isocyanates. Which mechanism best explains this sensitization-based condition?
- Acute toxicity from a single high-dose event
- IgE-mediated or non-IgE immune sensitization after repeated exposure (Correct answer)
- Carbon monoxide displacement of oxygen in hemoglobin
- Fibrogenic dust accumulation in alveoli
Correct answer: IgE-mediated or non-IgE immune sensitization after repeated exposure
Isocyanate-induced occupational asthma typically results from immune sensitization (IgE or non-IgE mediated) following repeated low-level exposures.
Question 3: Which NIOSH classification of half-facepiece air-purifying respirator is appropriate for protection against oil-based aerosols and non-oil particulates?
- N95
- R95
- P100 (Correct answer)
- N100
Correct answer: P100
P-series (P100) respirators are rated for use against oil and non-oil aerosols and filter at least 99.97% of airborne particles.
Question 4: A facility's emergency action plan requires sheltering-in-place during an accidental toxic gas release. Which action best reduces indoor infiltration of the outdoor contaminant?
- Increase HVAC fresh-air intake to dilute indoor air
- Seal doors, windows, and turn off HVAC to minimize infiltration (Correct answer)
- Open windows on the downwind side for cross-ventilation
- Activate the exhaust fans to purge contaminated air
Correct answer: Seal doors, windows, and turn off HVAC to minimize infiltration
During shelter-in-place, turning off HVAC and sealing openings minimizes the ingress of contaminated outdoor air.
Question 5: Chronic occupational exposure to asbestos is most strongly associated with which trio of diseases?
- Silicosis, emphysema, and lung cancer
- Asbestosis, mesothelioma, and lung cancer (Correct answer)
- Byssinosis, COPD, and pleural effusion
- Hypersensitivity pneumonitis, asthma, and sarcoidosis
Correct answer: Asbestosis, mesothelioma, and lung cancer
Long-term asbestos exposure is classically linked to asbestosis (fibrosis), malignant mesothelioma, and lung cancer.
Question 6: Under EPA's Risk Management Program (RMP), a facility storing more than a threshold quantity of a regulated toxic substance must develop which key document?
- Toxic Release Inventory (TRI) report
- Risk Management Plan including worst-case scenario analysis (Correct answer)
- Title V Operating Permit application
- Stormwater Pollution Prevention Plan (SWPPP)
Correct answer: Risk Management Plan including worst-case scenario analysis
Facilities exceeding RMP threshold quantities must develop a Risk Management Plan that includes worst-case and alternative release scenario analyses.
Question 7: A personal air sampling pump must be calibrated before and after each sample collection. Which calibrator is considered the primary standard for flow rate verification?
- Rotameter
- Electronic mass flow meter
- Soap-bubble or electronic primary standard calibrator (Correct answer)
- Pitot tube manometer
Correct answer: Soap-bubble or electronic primary standard calibrator
Primary standard calibrators such as soap-bubble meters or electronic equivalents (e.g., DryCal) directly measure volumetric flow and are used as primary references.
AQS Health & Safety Protocols 3
An air quality specialist is reviewing stack emission data and finds benzene emissions exceed the NESHAP limit.
Benzene is classified as which type of pollutant under the Clean Air Act?