HAZWOPER Decontamination Procedures & PPE Usage 4 — Questions and Answers
Question 1: Which factor most significantly determines the number of decontamination stations required at a hazardous waste site?
- The number of personnel on site
- The level of PPE worn and the type of contaminants involved (Correct answer)
- The size of the exclusion zone perimeter
- The distance from the nearest hospital
Correct answer: The level of PPE worn and the type of contaminants involved
The PPE ensemble worn and the chemical properties of the contaminants dictate how many removal and washing steps are needed for safe decontamination of workers and equipment.
Question 2: A Level C PPE ensemble differs from Level B primarily in that Level C uses:
- A fully encapsulating suit instead of splash-protective clothing
- An air-purifying respirator instead of supplied-air or SCBA (Correct answer)
- Supplied air respirator instead of SCBA
- Double-layer chemical gloves instead of single-layer
Correct answer: An air-purifying respirator instead of supplied-air or SCBA
Level C uses an air-purifying respirator (APR or PAPR) rather than supplied-air equipment, and is appropriate only when atmospheric contaminants and concentrations are known and the APR can adequately filter them.
Question 3: What does 'permeation' mean in the context of chemical protective clothing?
- Visible tearing or puncture of the suit material
- Molecular movement of a chemical through the suit material without visible damage (Correct answer)
- The absorption of decontamination solution into the suit
- Chemical reaction that dissolves the outer surface of the suit
Correct answer: Molecular movement of a chemical through the suit material without visible damage
Permeation is the process by which a hazardous chemical passes through protective clothing material at the molecular level without causing visible damage, making it a critical consideration in suit selection.
Question 4: Which decontamination solution is commonly used for general surface decontamination when the contaminant is an organochlorine pesticide?
- Dilute hydrochloric acid
- Dilute bleach (sodium hypochlorite) solution (Correct answer)
- Isopropyl alcohol
- Sodium hydroxide solution
Correct answer: Dilute bleach (sodium hypochlorite) solution
Dilute sodium hypochlorite (bleach) solution is effective for decontaminating many organic compounds including organochlorine pesticides through oxidation and chemical destruction.
Question 5: In the context of HAZWOPER decontamination, what is 'contamination reduction corridor'?
- The buffer zone between hot and cold zones where decontamination takes place (Correct answer)
- A narrow walkway used to limit movement of contaminated personnel
- The path workers take when entering the hot zone
- A chemical storage area within the warm zone
Correct answer: The buffer zone between hot and cold zones where decontamination takes place
The contamination reduction corridor is the designated area within the warm zone where decontamination stations are set up and workers transition from the hot zone to the clean cold zone.
Question 6: Which action by an instructor during a HAZWOPER 40-hour training would BEST demonstrate the correct procedure for heat stress monitoring in Level A PPE?
- Showing a video of workers resting between tasks
- Demonstrating pre-entry vital signs and post-exit comparison with set action thresholds (Correct answer)
- Instructing students to drink water before entering the hot zone
- Having students time how long they can wear Level A before feeling uncomfortable
Correct answer: Demonstrating pre-entry vital signs and post-exit comparison with set action thresholds
The proper procedure involves recording baseline vital signs (heart rate, temperature, weight) before entry and comparing them to post-exit measurements against established action thresholds for work/rest decisions.
Question 7: A contaminated drum is being opened in the hot zone. Workers notice vapor rising from the drum. Which respiratory protection is required if atmospheric monitoring shows concentrations above the IDLH?
- Half-face APR with organic vapor cartridges
- Full-face APR with combination cartridges
- Powered air-purifying respirator (PAPR)
- Supplied-air respirator or SCBA operating in pressure-demand mode (Correct answer)
Correct answer: Supplied-air respirator or SCBA operating in pressure-demand mode
At concentrations above the IDLH, only atmosphere-supplying respirators (SCBA or supplied-air) in pressure-demand mode provide adequate protection; air-purifying respirators are not permitted above IDLH.
HAZWOPER Decontamination Procedures & PPE Usage 4
Which factor most significantly determines the number of decontamination stations required at a hazardous waste site?