CPR CPR Equipment Selection & Deployment 2 — Questions and Answers
Question 1: A HEPA vacuum is required rather than a standard shop vacuum when:
- Vacuuming dry debris from hardwood floors
- Removing dry mold-contaminated material or lead-dust debris to prevent cross-contamination (Correct answer)
- Cleaning up Category 1 water spill residue
- Vacuuming soot from exterior brick
Correct answer: Removing dry mold-contaminated material or lead-dust debris to prevent cross-contamination
HEPA vacuums capture particles ≥0.3 microns at 99.97% efficiency, preventing mold spores or lead dust from being exhausted back into the air during cleanup.
Question 2: What does GPP (grains per pound) measure in restoration drying?
- The weight of water absorbed by building materials
- The moisture content of air — specifically, grains of water vapor per pound of dry air (Correct answer)
- The granular pore size of a desiccant material
- The grain weight rating of HEPA filter media
Correct answer: The moisture content of air — specifically, grains of water vapor per pound of dry air
GPP (grains per pound) is the specific humidity of air, expressing how many grains of water vapor are contained per pound of dry air, used to calculate dehumidifier efficiency.
Question 3: Negative air pressure containment in a mold remediation zone is achieved by:
- Sealing all windows and doors without exhaust
- Running an air scrubber/negative air machine exhausted to the outside so pressure inside is lower than surrounding areas (Correct answer)
- Using supply-air-only fans to pressurize the clean zone
- Turning off the building HVAC system
Correct answer: Running an air scrubber/negative air machine exhausted to the outside so pressure inside is lower than surrounding areas
Exhausting air to the outside with an air scrubber creates negative pressure, ensuring any air leakage flows INTO the containment zone rather than carrying spores out.
Question 4: When selecting a generator for powering restoration equipment on a job site without utility power, the FIRST calculation the restorer must make is:
- The fuel type available at the nearest gas station
- Total running wattage of all equipment plus a 20–25% startup surge buffer (Correct answer)
- The decibel rating for neighbor compliance
- Generator brand compatibility with air mover voltage
Correct answer: Total running wattage of all equipment plus a 20–25% startup surge buffer
Motors draw 2–3× their running wattage at startup; the restorer must total running watts and add a surge buffer to avoid tripping the generator under load.
Question 5: A moisture meter reads 16% on a hardwood floor subfloor. The dry standard for that region is 9–11%. This reading indicates:
- The material is dry and ready for flooring reinstall
- Elevated moisture content; continued drying is needed before reinstalling finished flooring (Correct answer)
- The meter is malfunctioning and should be recalibrated
- Readings above 15% are normal for subfloor materials
Correct answer: Elevated moisture content; continued drying is needed before reinstalling finished flooring
Subfloor moisture above the dry standard (typically 9–11% for hardwood substrates) indicates the material is not yet dry and flooring reinstallation would risk warping or mold.
Question 6: The Injectidry system (or similar wall-cavity drying panel) is used to dry:
- Exterior concrete foundations
- Enclosed wall and floor cavities without demolition by injecting and extracting airflow through small access holes (Correct answer)
- HVAC duct interiors
- Attic insulation batts
Correct answer: Enclosed wall and floor cavities without demolition by injecting and extracting airflow through small access holes
Injectidry panels attach to walls and create a controlled airflow circuit through small drilled ports, drying cavities while preserving the finished surface and reducing tear-out.
CPR CPR Equipment Selection & Deployment 2
A HEPA vacuum is required rather than a standard shop vacuum when: