Carbon Monoxide Poisoning

Toolbox Talk Record

Ref: TBT-OCC-012  |  Issue: 1  |  Date: March 2026
PresenterProject
LocationDate

What?

Why?

Silent killerCO is undetectable by human senses. Workers lose consciousness and die without ever knowing they were being poisoned.
Common hazardPortable generators and fuel-burning tools are used daily on construction sites, creating a constant CO exposure risk.
Rapid onsetCO poisoning causes confusion and drowsiness that prevent workers from recognising the danger and escaping in time.
Do Don't
  • Operate all generators and petrol tools outdoors in well-ventilated areas only.
  • Use CO detectors in any enclosed or semi-enclosed area where fuel-burning equipment operates.
  • Ensure adequate ventilation before and during use of any combustion equipment indoors.
  • Recognise the symptoms: headache, dizziness, nausea, and confusion indicate CO exposure.
  • Move anyone showing CO symptoms to fresh air immediately and call 999.
  • Position generator exhausts away from building openings, doors, and windows.
  • Maintain fuel-burning equipment to ensure efficient combustion and minimal CO output.
  • Test CO alarms regularly and replace batteries according to the manufacturer schedule.
  • Brief all workers on CO hazards, symptoms, and the location of CO detectors.
  • Use electric-powered alternatives to petrol and diesel tools wherever available.
  • DON'T run generators, engines, or petrol tools inside buildings or enclosed spaces.
  • DON'T ignore headaches, dizziness, or nausea when fuel-burning equipment is nearby.
  • DON'T position generator exhausts near windows, doors, or air intake points.
  • DON'T use fuel-burning heaters in site cabins without adequate permanent ventilation.
  • DON'T assume you will smell CO; it is completely odourless and undetectable.
  • DON'T re-enter an area where CO has been detected without confirming it is clear.
  • DON'T leave generators running unattended inside or near occupied spaces overnight.
  • DON'T block ventilation openings in spaces where combustion equipment is operating.
  • DON'T ignore CO detector alarms; evacuate immediately and investigate the source.
  • DON'T delay calling 999 for anyone showing CO poisoning symptoms.

See also: Occupational Health Awareness | Portable Generator Safety