DEFINITION
A preventive maintenance (PM) inspection is a scheduled check performed on a calendar interval or usage trigger (engine hours, mileage, cycles) to service equipment and catch wear before it causes failure — distinct from a regulatory safety inspection, though the two are often combined.
ALSO KNOWN AS · PM inspection · preventative maintenance · scheduled maintenance inspection
Preventive maintenance inspections are driven by time or usage rather than by an operator's daily go/no-go check. A PM schedule defines intervals — every 250 engine hours, every 5,000 miles, every 90 days, every so many lift cycles — at which the equipment is brought in for servicing: fluid and filter changes, lubrication, wear-component measurement, calibration, and a structured inspection of the systems that degrade with use.
PM is a reliability and cost discipline first: catching a worn wire rope, a failing hydraulic seal, or brake wear during a scheduled service is far cheaper and safer than the unplanned failure it prevents. But it also intersects with compliance — manufacturer maintenance intervals and ASME B30 periodic-inspection cadences both lean on a PM program, and a well-run PM history is strong evidence of due diligence in an audit or incident investigation.
Meter-driven PM is common for heavy equipment because runtime, not the calendar, best predicts wear. A crane, excavator, or generator accrues service obligations as its hour meter climbs, so the inspection schedule keys off the meter reading. Calendar-driven PM suits assets that degrade with time regardless of use, such as rigging gear or fire suppression.
PM inspections complement, rather than replace, the regulatory inspections: the daily/monthly/annual OSHA cadence verifies the equipment is safe to use today, while the PM program keeps it from getting there by servicing it on a planned interval. Many fleets run both from one schedule so a meter or date threshold triggers both the safety inspection and the maintenance service together.
FREQUENTLY · ASKED
A PM inspection is a scheduled, interval-based service to prevent wear-out failures. A safety inspection (daily, monthly, annual per OSHA or FMCSA) verifies the equipment is safe to operate. They overlap in scope and are often run together, but PM is reliability-driven while safety inspections are compliance-driven.
It depends on the asset. Equipment whose wear tracks runtime — cranes, excavators, generators — is best on meter-driven (engine-hour) PM. Assets that degrade with time regardless of use, like rigging or extinguishers, suit calendar-driven PM. Many programs use whichever interval comes first.
RELATED · TERMS
OSHA 1910.178 is the powered-industrial-truck standard covering forklifts and similar trucks. Section 1910.178(q)(7) requires that each truck be examined at least daily before being placed in service, and removed from service if any condition adversely affects safety.
A load chart is the manufacturer's table of a crane's rated lifting capacity for every combination of boom length, lift radius, and configuration. It defines the maximum weight the crane may safely hoist at each geometry and is the reference for determining percent-of-capacity on any lift.
ASME B30 is the consensus safety standard series for cranes, derricks, hoists, hooks, slings, and rigging. Each volume addresses a class of equipment — B30.2 overhead and gantry cranes, B30.3 tower cranes, B30.5 mobile and locomotive cranes — and OSHA incorporates several volumes by reference.
Lockout/Tagout (LOTO) is the OSHA-required practice of isolating and de-energizing machinery so it cannot start up during service or maintenance. Under 29 CFR 1910.147, each energy-isolating device is locked and tagged, protecting workers from the unexpected release of hazardous energy.
PUT · IT · TO · WORK
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