Calculation support, not a guaranteed safety decision.

A direct control is specifically targeted at the energy source, effectively prevents contact or release when installed, verified and used, and still works when someone makes a mistake. That last part is the test that most answers fail: training, signage, attentiveness and everyday PPE all assume nobody has a bad day. The examples below show the difference for each energy source. Qualifying examples are typical, not exhaustive, and site procedures decide what is acceptable.

Gravity

Qualifies

  • Exclusion zone under the load path, physically marked and maintained.
  • Tool tethers and secondary retention on items at height.
  • Installed edge protection with toe boards.

Does not qualify alone

  • Watching the load.
  • Hard hats alone.
  • A spotter shouting warnings.

Motion

Qualifies

  • Physical segregation between plant and people on foot.
  • Wheel chocks and skate stops applied before work near the load.
  • Traffic routes closed and barriered during heavy moves.

Does not qualify alone

  • High-visibility clothing alone.
  • Driver vigilance.
  • A banksman with no exclusion behind them.

Mechanical

Qualifies

  • Fixed guards over rotating and moving parts.
  • Isolation locked and verified before intervention.
  • Restraint applied before tension or spring load is released.

Does not qualify alone

  • Standing clear by judgement.
  • Gloves.
  • Working quickly.

Electrical

Qualifies

  • Isolation locked, tagged and proven dead at the point of work.
  • Insulated barriers over adjacent live parts.
  • Rated insulated tools and covers for work on systems that cannot be de-energised.

Does not qualify alone

  • Assuming dead because it was dead yesterday.
  • Signage alone.
  • Experience.

Pressure

Qualifies

  • Depressurisation verified at a gauge or vent at the point of work.
  • Exclusion zone during pressurisation and testing.
  • Whip restraints on temporary hoses and connections.

Does not qualify alone

  • Cracking a joint carefully.
  • Trusting a single gauge without verification.
  • Standing to the side.

Chemical

Qualifies

  • Lines and vessels proven empty before connections are broken.
  • Physical segregation of incompatible substances.
  • Local exhaust or forced ventilation for the substance in use.

Does not qualify alone

  • Generic PPE not matched to the substance.
  • Smelling for vapour.
  • Working fast to limit exposure.

Thermal

Qualifies

  • Combustibles removed or physically protected before hot work.
  • Guarding or barriers on hot and cryogenic surfaces.
  • Verified cool-down before contact work starts.

Does not qualify alone

  • A fire watch with combustibles left in place.
  • Warning signs on hot pipework.
  • Care.

Sound

Qualifies

  • A quieter method or tool substituted for the noisy one.
  • Enclosure or physical separation of the noisy work.
  • Noisy work scheduled away from occupied areas.

Does not qualify alone

  • Hearing protection alone.
  • Limiting exposure by judgement.

Radiation

Qualifies

  • Controlled area established and cleared before the source is exposed.
  • Shielding in place between source and people.
  • Welding screens physically positioned around arc work.

Does not qualify alone

  • Looking away from the arc.
  • Keeping exposure short by judgement.

Biological

Qualifies

  • Stagnant systems drained and flushed before opening.
  • Sealed handling and disposal of contaminated material.
  • Verified disinfection before work in affected systems.

Does not qualify alone

  • Gloves alone.
  • Holding your breath.
  • Washing afterwards.

PPE is the last barrier, not a control strategy. It reduces harm after every other layer has failed, which is exactly why Energy-Based Safety asks for a direct control first on every high-energy hazard. The narrow exception in the EEI guidance is specialised equipment-grade PPE, such as rated insulating gloves used within a verified live-working system, which can form part of a direct control.