2024 Commercial Mechanical Inspector – Practice Exam

1. Air-conditioning systems that supply required ventilation air must be provided with controls designed to automatically maintain the required outdoor air supply rate during which time period?

2. Where an oil-fired appliance is connected to an existing masonry chimney, the chimney flue shall be repaired or relined in accordance with which standard?

3. What is the capacity in thousands of Btu/h for 2-inch nominal Schedule 40 metallic pipe at 1,000 feet in length, for undiluted propane operating at 11.0 in. w.c. inlet pressure with a 0.5 in. w.c. pressure drop?

4. What is the minimum clearance required on the control side of a floor furnace?

5. A vented appliance designed for installation within the fire chamber of a vented fireplace, wherein the primary function lies in the aesthetic effect of the flames, is defined as a:

6. Which category of condensing appliances must be provided with an auxiliary drain pan where damage to any building component will occur as a result of a stoppage?

7. The passageway of domestic dryer exhaust duct terminals shall be undiminished in size and shall provide an open area of not less than what minimum size?

8. Metallic ducts for air distribution systems (other than those within single dwelling units) must be constructed as specified in which standard?

9. Which type of appliance is explicitly stated to not be governed by the methods of providing combustion air detailed in Chapter 7?

10. During what time period shall ventilation be provided for a room or space?

11. For an Animal exam room (veterinary office), what is the estimated maximum occupant load rate per 1,000 square feet?

12. Nonrecirculating direct-fired industrial air heaters shall not be used to supply any area containing what type of room?

13. For electrofusion joints, joint surfaces must be clean and free from moisture, and scoured to expose what material?

14. In addition to being experienced in conducting and supervising tests, personnel employed by an approved agency must be educated in evaluating what?

15. Taking return air from a kitchen is permitted if the return air openings serve the kitchen and are located not less than how far from the cooking appliances?

16. Motors for fans used to convey flammable vapors or dusts must be located outside the duct or protected with what?

17. Copper and copper alloy pipe shall not be used if the gas contains more than what average amount of hydrogen sulfide per 100 standard cubic feet of gas?

18. Where must the permit or a copy be kept until the completion of the project?

19. Shutoff valves used in fuel oil systems must comply with which UL standard?

20. TABLE 614.9.4.1 QUESTION: What is the equivalent length reduction required for a 6-inch radius smooth 90-degree elbow in a domestic dryer exhaust duct?

21. What is the minimum required thickness (in inches) for a galvanized steel vent connector with a diameter of 8 inches, serving a low-heat appliance?

22. Joints between dissimilar metallic piping materials must be made with a dielectric fitting or what other component conforming to dielectric tests of ASSE 1079?

23. Where a combination system requires water for space heating at temperatures higher than 140F, a temperature-actuated mixing valve conforming to ASSE 1017 must be provided to temper the potable hot water distribution system water to what maximum temperature?

24. In areas containing flammable vapors or dusts, motors driving exhaust fans shall be of a type approved for what?

25. Which types of equipment or appliances require condensate drain systems?

26. Variable air volume air distribution systems, other than those supplying 100-percent outdoor air, must be provided with controls to regulate the flow of outdoor air to maintain the flow rate at not less than that required by what section?

27. In machinery rooms using Group A2L and B2L refrigerants, open flame-producing devices or continuously operating hot surfaces shall not exceed what maximum temperature?

28. Where appliances are located on more than one floor and served by a common vent, the total available height (H) for each segment shall be measured from the highest draft hood outlet or flue collar entering that segment to which location?

29. In the exception for adjoining spaces, if an exterior opening opens into a thermally isolated sunroom addition, what is the minimum openable area required between the sunroom and the interior room?

30. Which repair garage is exempt from the requirement for a source capture system for motor vehicle operation?

31. Ventilation in dry cleaning plants must be adequate to protect employees and the public in accordance with this section and which other referenced standard, where applicable?

32. When entering an occupied structure or premises for inspection, the code official must first present credentials to the occupant and do what?

33. Welding on pressure vessels must be performed by an R-Stamp holder in accordance with the National Board Inspection Code, Part 3, or what other requirement?

34. For a single-appliance venting configuration, if the height (H) is less than 6 feet or greater than shown in the tables, what method must be used to calculate the vent capacity?

35. Metallic ducts installed underground and not having an approved protective coating must be completely encased in not less than how many inches of concrete?

36. What is the approximate length of the threaded portion required to be cut for a 1 1/4-inch iron pipe size?

37. If subject matter in a referenced standard is within the scope of this code, which provisions shall take precedence?

38. An existing chimney flue liner, inner wall, or vent inner wall must be continuous and free of cracks, gaps, perforations or other damage that would allow the escape of combustion products, including gases, moisture and:

39. Which type of boilers are required to be protected with a low-water cutoff control?

40. Large-diameter ceiling fans must be tested and labeled in accordance with AMCA 230, listed and labeled in accordance with UL 507, and installed according to what documentation?

41. What is the minimum clearance required between a single-wall metal pipe connector and combustible material when serving a residential boiler with a listed gas conversion burner and a draft hood?

42. When testing at a pressure greater than 100 psig (689.5 kPa gauge), the testing gauge must have increments of what maximum amount?

43. What must be provided for existing chimneys and vents in accordance with the International Building Code?

44. Where chemicals that generate corrosive or flammable products are routinely used, fired appliances where these chemicals can enter combustion air shall be located in a mechanical room that is partitioned off and provided with combustion air from:

45. What is the minimum length (in feet) of nominal 4-inch piping that, when removed from service, must have its residual fuel gas displaced with an inert gas?

46. The use of gypsum boards to form plenums is limited to systems where the air temperatures do not exceed what maximum temperature?

47. Nonmetallic ducts shall be constructed with which classes of duct material?

48. For chimney connector wall pass-through systems, insulation material that is part of the system shall be noncombustible and have a thermal conductivity of what maximum value?

49. Hazardous exhaust duct systems shall extend directly to the exterior of the building and shall not extend into or through what two building elements?

50. Air transported to occupied spaces through dust-producing materials by means other than natural convection shall be treated in what manner before entering the occupied space, in accordance with Section 605?