Mechanical, Electrical, and Plumbing (MEP) Systems
This domain covers the mechanical, electrical, and plumbing systems you can observe, operate safely, and describe, plus the limits on testing.
Mechanical
Typical equipment includes package rooftop units, split systems, chillers, boilers, cooling towers, VAV boxes, and exhaust fans. Record fuel, approximate capacity from nameplates, age, and condition. Note condensate leaks, refrigerant-line damage, combustion air, flue condition, and economizer dampers.
Electrical
Record service size, voltage, and phase from the main disconnect, along with switchgear, transformers, panels, generators, and UPS units. Look for double-tapped breakers, missing cover plates, rust, overheating, improper labeling, and blocked clearances. Do not remove deadfronts or operate breakers unless your scope and competence allow.
Plumbing
Domestic water, waste, vent, storm drainage, water heaters, backflow preventers, grease interceptors, sump pumps, and fuel gas are in scope. Check for active leaks, corrosion, improper supports, missing cleanouts, and cross-connections.
Worked example
An 800A, 120/208V three-phase service has no arc-flash label, a panel with two double-tapped breakers, and a missing knockout. Reasoning: report the observations as deficiencies; double taps may overload the breaker and are a fire hazard; missing labels impede safe maintenance. Recommend a licensed electrician evaluate and correct them. Do not calculate load or declare capacity adequate.
Traps
Operating valves or breakers; opening equipment you are not qualified for; quoting efficiency from a nameplate; and treating a recent service sticker as evidence of condition. Also: missing backflow prevention on an irrigation or boiler feed line.