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Module 8 of 8 90m 15 exam Qs

Health & Safety

Health and safety protocols for BPI AC and heat pump professionals including combustion safety testing, carbon monoxide detection, refrigerant safety, electrical safety, and worker protection requirements.

  • Perform combustion safety testing on gas appliances in the same building as HVAC equipment
  • Identify carbon monoxide hazards and appropriate response actions
  • Apply refrigerant safety protocols per EPA and ASHRAE standards
  • Follow electrical safety procedures when working on HVAC systems

Lesson 1

Combustion Safety Testing

Why AC Professionals Must Test Combustion Safety

BPI requires AC and heat pump professionals to test combustion safety even though their primary focus is cooling and heat pump systems. The reason is the house-as-a-system principle: changes to one system affect all others. Sealing ducts, changing airflow, or modifying the building envelope can change pressure relationships that affect combustion appliance operation.

For example, sealing return duct leaks in a home with an atmospheric gas water heater might solve the HVAC efficiency problem but create a combustion safety hazard. The sealed return duct no longer draws makeup air from the building cavity near the water heater, changing the pressure balance and potentially causing the water heater to backdraft.

Combustion Appliance Zone (CAZ) Testing

The Combustion Appliance Zone (CAZ) is the space where combustion appliances are located - typically the utility room, basement, or garage. BPI requires CAZ testing under worst-case depressurization conditions.

1
Establish Baseline
Measure ambient CO and natural draft conditions
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2
Create Worst Case
Close doors, run exhaust fans, run air handler
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3
Test Each Appliance
Draft, spillage, CO in flue gas
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4
Document Results
Record all measurements, pass or fail

Worst-case depressurization setup:

  1. Close all exterior doors and windows
  2. Close all interior doors to rooms with exhaust fans
  3. Turn on all exhaust fans (bathroom fans, kitchen range hood, dryer)
  4. Turn on the air handler (fan only)
  5. Measure the CAZ pressure relative to outdoors - this is the worst-case depressurization

What to Test

Draft measurement - Use a manometer or digital pressure gauge to measure draft in the vent connector. Negative pressure (draft) means combustion gases are going up the chimney. Positive pressure (zero or positive reading) means gases may be spilling into the building. Minimum acceptable draft is typically -1 to -3 Pascals.

Spillage testing - Hold a smoke pencil or match near the draft hood of each atmospheric combustion appliance. The smoke should be drawn into the draft hood and up the chimney. If smoke blows away from the hood or into the room, the appliance is spilling combustion gases.

CO in flue gas - Measure carbon monoxide concentration in the flue gas of each combustion appliance using a combustion analyzer. BPI action levels:

0 ppm
Ideal Ambient CO Level
35 ppm
EPA Ambient CO Action Level (8-hr)
100 ppm
Max CO Air-Free in Gas Flue
200 ppm
Max CO Air-Free in Oil Flue
Key Takeaway

BPI requires AC professionals to perform combustion safety testing because HVAC work can change building pressure relationships that affect combustion appliance operation. Test under worst-case depressurization (all exhausts running, interior doors closed, air handler on). Measure draft, spillage, and CO in flue gas for every combustion appliance. Ambient CO above 35 ppm requires immediate action.
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