Horizontal gas furnace installed in an attic between insulated rafters, with flexible supply ducts, a metal flue pipe and the gas valve compartment
Generic photo: Mark Doliner · CC BY-SA 2.0

Ladder safety on service calls: attic air handlers, range hoods, garage door openers and outdoor units

Falls from ladders are a leading cause of serious injury on the job, and service calls add tight spaces, live wiring and heavy parts. The core rules from OSHA's ladder standard and NIOSH: set an extension ladder at about a 4-to-1 angle (about 75 degrees), extend it at least 3 feet past the landing, face the ladder and keep three points of contact, never stand on a stepladder's top or top step, use a ladder rated for you plus your tools, and use a nonconductive (fiberglass) ladder around electricity.

Cross-checked ~5 min easyBrands: All

Before you start

  • Do not use aluminum ladders near overhead lines or exposed energized equipment
  • Do not carry heavy parts (OTR microwave, blower, opener) up a ladder alone; get a helper or a lift
  • Mark damaged ladders Do Not Use and take them out of service

Diagnostic steps

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Ladder safety on service calls: attic air handlers, range hoods, garage door openers and outdoor units · OnCall Tech