M2 Commercial Mechanical Inspector Questions and Answers

The ICC mechanical code requires condensate disposal components to be of approved corrosion-resistant material , and the drain line shall not decrease in size from the drain pan connection to the place of disposal. The code minimum size is 3/4 inch , so the 1/2-inch statement is incorrect, and the code is not limited to PVC only. Also, the slope requirement for horizontal drain piping is not less than 1/8 inch per foot , not 1/4 inch per foot. That makes Option A the only fully correct statement.

The IFGC section on test medium states that the test medium shall be air, nitrogen, carbon dioxide or an inert gas , and specifically states that oxygen shall not be used as a test medium . That makes C the correct answer.

Vent connectors must be installed with a minimum rise of 1/4 inch per foot . For a 10-foot run, the required rise is:

10 × 1/4 inch = 2.5 inches .

That equals 2-1/2 inches , so Option D is correct.

The ICC mechanical administrative inspection sequence includes underground inspection , rough-in inspection , and final inspection as required inspections. An annual system test is not listed as one of the required permit inspections in that section, so Option D is the correct answer. This fits the M2 General Administration content area, which includes permit and inspection administration.

For indoor combustion air openings, one opening must commence within 12 inches of the top of the enclosure and one within 12 inches of the bottom . That corresponds to 1 foot of the ceiling and 1 foot of the floor , so Option A is correct.

Under the ICC administrative provisions used with the mechanical code, one approved set is retained by the code official, and one approved set is returned to the applicant. The returned set must be kept on the site of the building or job while the authorized work is in progress. That directly matches Option A . It does not require return to the architect, filing with the county clerk, or retention for one year after completion.

Based on the equipment schedule shown in the exhibit, EF-2 is listed with a motor size of 1.5 horsepower . Therefore, the correct answer is C .

For a Type B gas vent with a listed vent cap terminating through a flat roof , the minimum required termination height is 1 foot above the roof . That makes Option A correct. This is consistent with gas vent termination tables used with listed Type B vent systems and the code framework for Type B vent terminations.

For materials such as pipe and duct insulation within plenums, the IMC references ASTM E84 or UL 723 for surface-burning characteristics, along with the flame-spread and smoke-developed limits applicable to plenums. ASTM B84 is not the referenced plenum test standard here, so it is the incorrect condition and therefore the correct exam answer to the “except” question. This makes Option C correct.

For commercial kitchen exhaust associated with Type I hood systems, the recognized code-based minimum duct transport velocity is 1,500 feet per minute , so C is the correct answer. Option B uses the wrong unit, and the other listed velocities do not match the code minimum used for this question type.

For appliances on roofs, ICC access provisions require a level platform at the appliance. The platform must be not less than 30 inches in any dimension . For the choices provided, that makes 30 inches the correct answer, which is Option C .

For this type of continuously ventilated exhaust shaft serving a multifamily building, the code requires the kitchen exhaust connection to penetrate the shaft and extend vertically not less than 22 inches without a fire damper. That matches Option D .