HERS Ventilation & Indoor Air Quality 3

Question 1

Combustion safety testing for atmospherically vented heating appliances in a home primarily evaluates:

Accepted Answer

Carbon monoxide production during normal operation and worst-case depressurization

Answer

Combustion safety testing checks whether vented appliances produce or spill CO under both normal and worst-case depressurization conditions, protecting occupants from CO poisoning.

Question 2

Per BPI standards, what ambient CO concentration measured in the living space triggers an 'Immediate Action Required' response during combustion safety testing?

Accepted Answer

35 ppm

Answer

BPI protocols designate 35 ppm as the ambient CO threshold requiring immediate action, based on OSHA permissible exposure limits to protect occupant health.

Question 3

Which indoor air quality pollutant is of primary concern in homes with attached garages or gas-fired combustion appliances?

Accepted Answer

Carbon monoxide (CO)

Answer

Carbon monoxide from vehicle exhaust in attached garages or incomplete combustion in appliances is an immediately life-threatening pollutant that HERS raters are trained to identify.

Question 4

Radon gas mitigation in a residential building is most effectively achieved by installing:

Accepted Answer

A sub-slab depressurization (SSD) system that vents soil gases to the exterior

Answer

Sub-slab depressurization creates negative pressure beneath the foundation slab, preventing radon from entering the living space and exhausting it safely to the outdoors.

Question 5

Per ASHRAE 62.2, the infiltration credit allows a reduction in required mechanical ventilation airflow when measured envelope leakage exceeds:

Accepted Answer

2 CFM25 per 100 sq ft of floor area

Answer

ASHRAE 62.2 Section 4.1.3 allows an infiltration credit to offset mechanical ventilation requirements when the home's measured leakage exceeds 2 CFM25 per 100 sq ft, recognizing natural air exchange contribution.

(HERS) Home Energy Rater Certification Practice Test

(HERS) Home Energy Rater Certification Practice Test

HERS Ventilation & Indoor Air Quality 3