Combustion Safety Flashcards

What is the primary purpose of a spillage test during a combustion safety evaluation?

Answer: To determine if combustion gases are escaping into the living space

A spillage test determines whether combustion gases are spilling from the appliance draft hood or diverter into the conditioned space instead of venting properly.

Which condition is most likely to cause backdrafting in a naturally drafted water heater?

Answer: Negative pressure in the mechanical room due to exhaust fans

Exhaust fans depressurize the building, creating negative pressure that can reverse flue draft and pull combustion gases into the living space.

What CO concentration (ppm) in ambient air immediately requires evacuation and emergency response per BPI standards?

Answer: Action level varies but life-safety response triggers at undiluted flue readings over 400 ppm with ambient spillage

BPI protocols require immediate occupant evacuation and emergency service notification when undiluted flue CO exceeds 400 ppm and gases are spilling into the living area.

A BPI analyst measures CO in the undiluted flue of a gas furnace and reads 250 ppm. What is the correct action?

Answer: Tag the unit as unsafe and advise the homeowner to have it serviced

BPI's action level for undiluted flue CO is over 400 ppm; at 250 ppm the unit is elevated but below immediate life-safety threshold, so the analyst tags it and recommends HVAC service.

What does the Building Performance Institute define as 'worst-case depressurization'?

Answer: The most negative pressure achievable in the combustion appliance zone under realistic operating conditions

Worst-case depressurization is the maximum negative pressure that can be induced in the combustion appliance zone by simultaneously operating all exhaust equipment and closing interior doors.

Which instrument is required to measure worst-case depressurization in a combustion appliance zone?

Answer: Digital manometer

A digital manometer (pressure gauge) measures the pascals of pressure difference between the combustion appliance zone and outdoors during worst-case conditions.

A gas range without a vented hood is considered what type of combustion appliance under BPI protocols?

Answer: Unvented combustion appliance

A gas range vents combustion products directly into the kitchen, making it an unvented appliance that contributes to indoor air quality concerns.