RISK – Not isolating effectively
Identifying isolation points can be achieved in a number of ways, including walkthroughs, reviewing piping and instrumentation diagrams and schematics.
Other ways to identify isolation points include:
- Review operating manuals
- Talk to operating authorities
- Obtain assistance from dial before you dig (or equivalent) in identifying buried services, performing visual observations
- Obtain visual confirmation
Hazardous materials and energy sources can include:
- Electricity – mains and stored (UPSs, batteries and capacitators)
- Fuels
- Extreme heat or cold
- Steam
- Fluids and gases under pressure (water, steam, air, hydraulic fluids)
- Stored kinetic energy (springs, counterweights, Winch & Cables)
- Moving machinery
- Radiation and biological hazards
The stages of isolating a service are:
Test for Dead
The Permit Holder, or Isolation Officer on complex sites, must confirm the isolation (zero energy state – electrical, mechanical or potential stored energy) of the equipment.
Attach isolation tags and locks
Lock and tag colours stipulated in the John Holland Isolation Procedure are:
- Personal– red
- Permit Holder – purple
- Multi-point Isolation – black
- Isolation Officer – orange
- Construction zone separation – pink tag and brass lock
Each person in the workgroup must fix their red personal danger lock and tag to the isolation point (single point isolation) or designated lock box (multi-point isolation) as indicated by the isolation permit.
The red Personal danger lock and tag are only to be placed and removed by the person whose name appears on the tag.
Lock out and tag out equipment
Related GMRs
8.5 Assess machinery for components with potential stored energy under tension or pressure
Related Procedures / Forms