What is lockout tagout?
Lockout tagout is how you make a machine safe before someone works on it. Every energy source is isolated, locked off with a personal padlock and tagged, stored energy is released, and the isolation is proved before work starts. HSE calls this safe isolation, and its guidance HSG253 sets out the principles.
This is a template, so adapt it to your own procedure, equipment and risk assessment, and have a competent person approve it, before anyone uses it.
When: before maintenance, cleaning, clearing a blockage or any work where the machine could start up or release stored energy.
Before you start
The isolation procedure or isolation sheet for this machine, your own padlock and tag, a multi-lock hasp if more than one person is working, and an approved voltage indicator and proving unit if you are competent to carry out electrical tests.
Steps
- Identify every energy source: electrical, hydraulic, pneumatic, stored mechanical (springs and flywheels), gravity (raised parts), thermal and chemical. Use the isolation sheet rather than memory.
- Tell people. Let the operators and anyone else affected know the machine is being isolated.
- Stop the machine using its normal controls.
- Isolate. Put each isolating device into the off position.
- Lock and tag. Fit your own padlock and tag to every isolation point. If others are working, each person fits their own lock to a multi-lock hasp.
- Release or restrain stored energy. Bleed hydraulic and air pressure, lower or block raised parts, let moving parts come to rest and let hot parts cool.
- Prove the isolation. Try the start controls, check that pressure gauges read zero and, for electrical work, test for dead using prove, test, prove.
- Do the work.
- Before restoring, check that tools and materials are removed, guards are refitted and everyone is clear.
- Remove locks and restore. Each person removes only their own lock. Tell the operators, then restore energy and test the machine.
Never remove someone else's lock, treat a stop button or emergency stop as an isolation, or work on a machine that is only switched off at the control panel.
Toolbox talk
- Which machines here have more than one energy source?
- What do you do if you find a lock on an isolator and its owner has gone home?
- Where are the isolation sheets kept for this area?
Further reading: HSE HSG253, The safe isolation of plant and equipment, and HSG85, Electricity at work: safe working practices.
These templates are general outlines for UK workplaces, provided free and without warranty. They do not replace your own risk assessment, training, supervision, permit systems or manufacturers' instructions. You are responsible for checking and approving any guide before it is used.