CPR CPR Odor Control & Deodorization 2 — Questions and Answers
Question 1: What is the primary purpose of an air scrubber (negative air machine) during smoke odor remediation?
- To heat the structure for drying
- To filter airborne particulates and odor-laden air using HEPA and activated carbon filters (Correct answer)
- To inject ozone into the work area
- To measure VOC levels in the air
Correct answer: To filter airborne particulates and odor-laden air using HEPA and activated carbon filters
Air scrubbers draw contaminated air through HEPA and carbon filtration stages, capturing particulates and adsorbing volatile organic compounds that carry odors.
Question 2: Which biological odor situation calls for an EPA-registered antimicrobial applied BEFORE deodorization?
- Cigarette smoke odor in walls
- Category 3 sewage intrusion with microbial contamination (Correct answer)
- Cooking odors in kitchen cabinets
- Pet dander odors in carpet
Correct answer: Category 3 sewage intrusion with microbial contamination
Category 3 water (sewage) contains pathogens; antimicrobial treatment must precede deodorization to address the biological source, not just the smell.
Question 3: Activated carbon filtration in air scrubbers works by which mechanism?
- Chemical oxidation of VOC molecules
- Adsorption — VOC molecules physically bond to the large porous carbon surface (Correct answer)
- UV photolysis of odor compounds
- HEPA mechanical filtration of gas molecules
Correct answer: Adsorption — VOC molecules physically bond to the large porous carbon surface
Activated carbon captures VOCs through adsorption, where gas-phase molecules adhere to the extensive internal surface area of porous carbon granules.
Question 4: After ozone treatment ends and the area is ventilated, how is residual ozone best confirmed safe before re-occupancy?
- Wait 15 minutes and rely on the smell
- Test with a calibrated ozone meter until levels fall below 0.1 ppm OSHA PEL (Correct answer)
- Run an air scrubber for 1 hour
- Open all windows for 5 minutes
Correct answer: Test with a calibrated ozone meter until levels fall below 0.1 ppm OSHA PEL
OSHA's permissible exposure limit for ozone is 0.1 ppm (8-hour TWA); a calibrated meter confirms safe levels before occupants return.
Question 5: A restorer detects a strong musty odor after completing Category 2 water mitigation. The MOST likely source is:
- Residual cleaning chemical off-gassing
- Microbial growth (mold/bacteria) in remaining wet materials (Correct answer)
- Ozone from equipment left running
- Glue off-gassing from new flooring installed nearby
Correct answer: Microbial growth (mold/bacteria) in remaining wet materials
Musty odors following water damage are a hallmark sign of microbial amplification in materials that remained wet beyond the 24–48 hour window.
Question 6: Which standard governs professional smoke and odor remediation procedures for restorers in the US?
- NFPA 921
- IICRC S770 Standard for Professional Smoke Remediation (Correct answer)
- OSHA 29 CFR 1910.134
- EPA 40 CFR Part 61
Correct answer: IICRC S770 Standard for Professional Smoke Remediation
The IICRC S770 Standard for Professional Smoke Remediation establishes the industry's technical requirements for smoke and odor assessment and remediation.
CPR CPR Odor Control & Deodorization 2
What is the primary purpose of an air scrubber (negative air machine) during smoke odor remediation?