Practice Test Geeks(313D) Residential Air Conditioning Systems Mechanic Certification Practice Test
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Safety and Regulations Flashcards

7 cards from real 313D practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Safety and Regulations flashcards as text

  1. What does the ASHRAE Standard 15 primarily govern in HVAC applications?

    Answer: Safety code for mechanical refrigeration systems

    ASHRAE Standard 15 is the Safety Standard for Refrigeration Systems, covering safe design, construction, installation, and operation of refrigerating systems.

  2. Under the NEC, which article specifically addresses wiring methods and equipment for air conditioning and refrigerating equipment?

    Answer: Article 440

    NEC Article 440 covers air conditioning and refrigerating equipment, including motor circuits and overcurrent protection requirements specific to hermetic refrigerant motor compressors.

  3. A residential split system's outdoor disconnect must be located within sight of and within how many feet of the equipment?

    Answer: 50 feet

    The NEC requires the disconnecting means to be within sight of and within 50 feet of the air conditioning equipment it serves.

  4. Which refrigerant classification under ASHRAE 34 indicates the highest flammability level?

    Answer: Class 3

    ASHRAE 34 Class 3 refrigerants are highly flammable, with a flame propagation rate greater than 10 cm/s and heat of combustion ≥19 kJ/g.

  5. What is the purpose of a relief valve on a refrigerant receiver or storage tank?

    Answer: To vent refrigerant when pressure exceeds safe limits

    Relief valves are safety devices that open to release refrigerant when pressure exceeds a preset limit, preventing vessel rupture.

  6. According to OSHA, what is the permissible exposure limit (PEL) for R-22 (chlorodifluoromethane) over an 8-hour workday?

    Answer: There is no established OSHA PEL for R-22

    OSHA has not established a specific PEL for R-22; however, ACGIH has a TLV of 1,000 ppm and manufacturers recommend limiting exposure based on SDS data.

  7. When brazing copper refrigerant lines in a residential system, which safety practice is specifically required to prevent refrigerant decomposition into toxic by-products?

    Answer: Purge lines with dry nitrogen during brazing

    Purging with dry nitrogen during brazing prevents oxidation scale formation inside the tubing and prevents residual refrigerant from decomposing into toxic gases like phosgene.