EK

Midterm study guide

  1. Why are all HVACR tradesmen advised to enroll in an approved first-aid course? Quick and proper treatment of injuries can result in less pain and possibly save lives
  2. Safety protection should be worn: At all times when performing any work that requires PPE.
  3. How can maintaining an orderly shop be beneficial? Less time is wasted searching for required tools or materials.
  4. When should you read the SDS for a particular chemical product? Before using the product
  5. How can you determine what PPE should be used with any particular chemical product? Read the SDS form for that product
  6. When working with tools, a safety procedure to follow is to: Always read the manufacturer's instructions
  7. Why should tools only be used for the jobs they were intended to perform? They have not been tested for safety for jobs they were not designed for.
  8. Before changing the blade in an electric circular saw, you should: Unplug the saw
  9. The base of an extension ladder that is correctly set up will be: 1 foot from the wall for every 4 feet in length.
    1. The top of an extension ladder: Should extend at least 36 inches above the point where it rests on the building.
    2. How can a confined space, such as a walk-in cooler or underground tunnel, become a safety hazard? The oxygen is limited—long exposure can cause suffocation
    3. Match the fire extinguisher class with the type of fire. Combustible metals:Class D Flammable liquids:Class B Ordinary combustibles: Class A Electrical fires: Class C
    4. Why should oil or grease never be used to lubricate oxygen or acetylene regulators? It can react with certain chemicals or materials and result in an explosion.
    5. Why might a bad driving record make it difficult to get a job at a service company? Your driving record affects the cost of insurance to the company.
    6. In case of an accident, the first step is: Call 911.
    7. Which types of accidents should be reported? All accidents
    8. What is a service valve wrench? A ratchet wrench with square openings that fit service valve stems
    9. What are the most common sizes of standard sockets? From 1/4 in up to 1 in in 1/16-in increments
    10. What is the difference between a flare-nut wrench and a standard box wrench? The flare wrench heads are slotted to slip over the tubing.
    11. Why are mushroomed chisel heads dangerous? Chips may break off.
    12. What should be done with damaged tools? Throw them away.
    13. Why should pliers NOT be used to tighten bolts and nuts? They will round off the corners.
    14. A barometer is used to read:Atmospheric pressure.
    15. Define a vacuum. A vacuum is any pressure less than atmospheric pressure
    16. The specific gravity of water is: 1.0
    17. When gas exerts pressure on its container, the pressure is: Distributed equally on all surfaces of the container.
    18. Atmospheric pressure is created by: The weight of the air in the atmosphere
    19. The first law of thermodynamics states that: Energy cannot be created or destroyed
    20. The absolute temperature scale for Fahrenheit is: Rankine
    21. Convert 40° Celsius to Fahrenheit. 40 × 1.8 = 72; 72 + 32 = 104°F
    22. Atmospheric pressure is affected by: Altitude, temperature, and humidity.
    23. According to Pascal's law, what happens to the pressure of a propane tank as it empties? The pressure remains uniform throughout the tank.
    24. Convert 40° Fahrenheit to Celsius. 40 - 32 = 8; 8/1.8 = 4.4°C
    25. It is important to the HVACR technician to understand the changes of state of matter because: The cooling and heating process requires a change of state of matter in some form.
    26. The three basic methods of heat transfer are: Conduction, convection, and radiation.
    27. What is absolute zero? The coldest temperature possible where all molecular motion stops
    28. The total pressure in a mixture of gases is equal to: The sum of all the individual gas partial pressures.
    29. According to the second law of thermodynamics, how does heat travel? Heat energy travels from a warmer body to a cooler body.
    30. What is the relationship between atoms and molecules? Molecules are made up of atoms.
    31. The law of conservation of matter states that: Matter cannot be created or destroyed.
    32. The nucleus of an atom: Is composed of protons and neutrons.
    33. The curved oval metal tube inside a gauge is called: A Bourdon tube.
    34. A thorough knowledge of the properties of matter is necessary to: Better understand what happens to various forms of matter and the reasons why changes occur when substances are heated or cooled.
    35. The absolute temperature scale for Celsius is: Kelvin
    36. The definition of sublimation is: A substance in a solid state changes into the gaseous state without going through the liquid state.
    37. Matter cannot be created or destroyed, but it can and does change form. This statement is known as: The law of conservation of matter.
    38. Standard atmospheric pressure at sea level with a temperature of 59°F is: 14.7 psia or 29.92 in Hg.