ASCS Risk Management & Mitigation 2 — Questions and Answers
Question 1: A technician discovers standing water inside a supply air duct during an inspection. What is the MOST appropriate initial risk mitigation step?
- Immediately seal the duct and mark it out of service
- Document the finding, identify the moisture source, and recommend remediation before cleaning (Correct answer)
- Proceed with cleaning using a HEPA vacuum to remove the water
- Notify the building owner and continue with the scheduled cleaning
Correct answer: Document the finding, identify the moisture source, and recommend remediation before cleaning
Standing water indicates an active moisture intrusion problem that must be sourced and corrected before cleaning to prevent recontamination and mold growth.
Question 2: Which type of risk assessment tool uses a grid to plot the probability of a hazard against its potential severity?
- Fault tree analysis
- Risk matrix (Correct answer)
- Job hazard analysis (JHA)
- Bowtie diagram
Correct answer: Risk matrix
A risk matrix plots likelihood versus consequence to help prioritize which risks require immediate mitigation action.
Question 3: When cleaning HVAC systems in a hospital, which patient area classification presents the HIGHEST biological risk requiring the most stringent containment?
- Administrative offices
- General patient wards
- Operating rooms and immunocompromised patient suites (Correct answer)
- Cafeteria and public lobbies
Correct answer: Operating rooms and immunocompromised patient suites
Operating rooms and areas housing immunocompromised patients are the most vulnerable environments, requiring maximum containment to prevent airborne pathogen exposure.
Question 4: A risk residual is best defined as:
- The total risk present before any controls are applied
- The level of risk that remains after all mitigation measures have been implemented (Correct answer)
- The estimated cost of a potential incident
- The probability that a hazard will occur within a given timeframe
Correct answer: The level of risk that remains after all mitigation measures have been implemented
Residual risk is what remains after controls are in place, and it must be deemed acceptable before work proceeds.
Question 5: An ASCS technician notices significant visible mold inside a commercial air handling unit. Under NADCA standards, what is the correct course of action?
- Clean the mold using standard mechanical brushing and vacuum extraction
- Apply an EPA-registered antimicrobial coating and proceed with normal cleaning
- Stop work, notify the client, and recommend a licensed mold remediation contractor (Correct answer)
- Increase negative pressure and clean using HEPA-filtered equipment without interruption
Correct answer: Stop work, notify the client, and recommend a licensed mold remediation contractor
NADCA ACR 2021 requires that visible mold contamination be referred to a qualified remediation contractor before HVAC cleaning proceeds.
Question 6: Which engineering control BEST reduces the risk of cross-contaminating clean areas when cleaning a return air duct system?
- Using a HEPA-filtered vacuum at the point of cleaning
- Establishing negative air pressure in the duct system during cleaning (Correct answer)
- Spraying a biocide into the ductwork before brushing
- Sealing all supply registers with magnetic covers
Correct answer: Establishing negative air pressure in the duct system during cleaning
Negative air pressure contains dislodged contaminants within the duct system, preventing them from escaping into occupied spaces.
Question 7: Which document specifically outlines the hierarchy of controls that ASCS professionals should apply when addressing HVAC system hazards?
- EPA Indoor Air Quality Guide
- OSHA 29 CFR 1910.132 PPE standard
- NADCA ACR 2021 Assessment, Cleaning, and Restoration of HVAC Systems (Correct answer)
- ASHRAE 62.1 Ventilation for Acceptable Indoor Air Quality
Correct answer: NADCA ACR 2021 Assessment, Cleaning, and Restoration of HVAC Systems
NADCA ACR 2021 is the primary standard governing HVAC cleaning practices, including risk assessment and the application of hazard controls.
A technician discovers standing water inside a supply air duct during an inspection.
What is the MOST appropriate initial risk mitigation step?