M2 Commercial Mechanical Inspector Questions and Answers

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.

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 .

The IMC specifically provides that Type I hoods used over extra-heavy-duty cooking appliances shall not cover other appliances requiring fire-extinguishing protection and shall discharge to an independent exhaust system . Therefore, D is correct.

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.

The IMC appliance provisions prohibit duct connection to a vented wall furnace . That makes Option B correct. The exam tests recognition of appliance-specific distribution restrictions rather than general duct rules.

The ICC administrative provisions require construction documents to be submitted in two or more sets with the permit application. After approval, one set is retained by the code official and one set is returned to the applicant to be kept on the job site during construction. That is exactly the condition described in Option D . The code does not state that all sets are retained by the code official or that the purpose is to provide subcontractor copies or backup copies.

A low-pressure steam heating boiler is defined as a boiler furnishing steam at pressures not exceeding 15 psi . That matches Option B .

The ICC mechanical code requires the lowest portion of a floor furnace to have not less than 6 inches (152 mm) clearance from grade level . Therefore, the correct choice is the option corresponding to 6 inches , which is C based on your answer set.

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.

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.

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 appliances listed for outdoor installation and incorporating integral venting , the IMC requires them to be installed in accordance with their listings and the manufacturer’s installation instructions . That matches Option C exactly.