RSES Code Compliance 2 — Questions and Answers
Question 1: Under ASHRAE 15, what is the maximum allowable refrigerant concentration limit (RCL) used for occupied spaces?
- The IDLH value
- The ATEL or ODL, whichever is lower (Correct answer)
- The TLV-TWA value
- The STEL value
Correct answer: The ATEL or ODL, whichever is lower
ASHRAE 15 uses the lower of the Acute Toxicity Exposure Limit (ATEL) or Oxygen Depletion Limit (ODL) as the RCL for occupied spaces.
Question 2: What does Section 608 of the Clean Air Act require technicians to do before disposing of appliances containing refrigerants?
- Label the appliance with refrigerant type
- Recover the refrigerant prior to disposal (Correct answer)
- Neutralize the refrigerant with nitrogen
- Vent residual refrigerant to atmosphere
Correct answer: Recover the refrigerant prior to disposal
Section 608 mandates that refrigerant must be recovered before any appliance is disposed of to prevent venting.
Question 3: Which EPA certification type covers technicians who service small appliances containing 5 lbs or less of refrigerant?
- Type I (Correct answer)
- Type II
- Type III
- Universal
Correct answer: Type I
EPA Section 608 Type I certification covers technicians servicing small appliances with 5 lbs or less of refrigerant.
Question 4: According to the International Mechanical Code, refrigeration machinery rooms must be provided with what minimum ventilation?
- 0.5 CFM per square foot of floor area
- Continuous mechanical ventilation at 0.5 CFM/sqft plus emergency purge at 1 CFM/sqft (Correct answer)
- Natural ventilation only via louvers
- 0.25 CFM per square foot continuous
Correct answer: Continuous mechanical ventilation at 0.5 CFM/sqft plus emergency purge at 1 CFM/sqft
The IMC requires a machinery room to have continuous ventilation of 0.5 CFM/sqft and emergency ventilation of 1 CFM/sqft activated by a detector.
Question 5: Under UL 207, pressure relief devices on refrigerant receivers must be set to open at no more than what percentage of the vessel's design pressure?
- 90%
- 100% (Correct answer)
- 110%
- 125%
Correct answer: 100%
UL 207 requires pressure relief devices to be set to open at no more than 100% of the vessel's design (maximum allowable working) pressure.
Question 6: Which refrigerant class under ASHRAE 34 poses the highest flammability risk?
- Class 1
- Class 2L
- Class 2
- Class 3 (Correct answer)
Correct answer: Class 3
ASHRAE 34 Class 3 refrigerants are highly flammable with a Lower Flammability Limit (LFL) below 3.5% and a heat of combustion at or above 19 kJ/g.
Question 7: When must an EPA Section 608 technician certification card be presented under federal regulations?
- Only when purchasing R-410A in containers over 2 lbs
- Upon request by the refrigerant seller or EPA enforcement officer (Correct answer)
- At every job site inspection
- Only when crossing state lines with refrigerant
Correct answer: Upon request by the refrigerant seller or EPA enforcement officer
Technicians must present their certification card upon request by a refrigerant seller or EPA enforcement authority.
RSES Code Compliance 2
Under ASHRAE 15, what is the maximum allowable refrigerant concentration limit (RCL) used for occupied spaces?