What is Lockout?
Explaining the Lockout Procedure
Lockout refers to the principle of shutting down an energy source correctly, draining any excess energy and applying devices to that energy source that prevent it from being energised.
In simpler terms, a lockout device stops something from being switched on when it is absolutely essential that it remains switched off.
Anything that is an energy source is eligible for lockout, as long as that energy source moves machinery and the components within that machinery. Energy sources can come in various forms, and range from everything from electrical, mechanical, hydraulic to pneumatic power. In short, if it is machinery that is in need of servicing and repair and it runs on an energy source, it is eligible for lockout.
Lockout itself is actually part of the grouping ‘Lockout, Tagout (LOTO)’ which is enforced by regulatory bodies. Under these regulations it is the responsibility of an employer to ensure that correct lockout/tagout procedures are taking place, which involves providing adequate training, the correct materials for locking out and clearly tagging any locked out energy sources with easily readable materials.
Avoiding Accidents Using Lockout
Every year there are many easily avoidable accidents that take place within working environments. These can be life threatening and can even be fatal, but could easily be prevented by the use of a lockout. Imagine for example that an engineer is working inside a machine. That machine may have moving pistons inside, which are stopped by the energy source being changed to an off switch. When locked out, the off switch stays that way until the lockout is removed when the engineer is done using the machinery. If the lockout was removed prematurely and the machinery was switched on, it is extremely likely that the engineer could be crushed by the pistons with the machine.
It doesn’t pay not to lockout. These accidents happen, and you should be using LOTO procedures whenever you need to.
There are many kinds of lockout devices available on the market, each of which is suitable for a different application. It is important that you always use the right lockout for the right application, as these help to secure the energy source firmly in place.
Following a Lockout Procedure
To lockout, there is usually a responsible individual elected to oversee the lockout. This person then attaches a lockout device to the energy source, secures it in place, and then applies a padlock that can only be opened with the person with the key. Other individuals assigned to the job should also apply their own padlock to the lockout, thus ensuring that they are represented as being part of the job.
This enables the individual employees working on a job to undo their padlock from the lockout only when their job is completed, thus ensuring that they won’t be working inside machinery when the lockout is removed and the energy source is switched back on.
When completing lockout, there is a certain way to go about doing the job to make sure everything is correctly shut down, and it safe to commence with the work.
Step 1: Prepare for the Shutdown
Firstly, you must identify what type of energy the machine uses. You must then identify exactly which switches, valves or anything else that releases energy actually power the machine, and then deduce which of these needs to be effectively locked out to stop energy from powering machinery.
This part of the planning is exceptionally important because it ensures that you clearly identify what needs to be locked out, and reduced the risk significantly of missing something that should be locked out.
Step 2: Communicate With Employees
After identifying energy sources necessary for lockout, you must inform any employees affected by the lockout why it is taking place, and also advise them not to touch any energy sources that might be locked out.
All employees should have adequate training in lockout procedures and should be able to clearly understand why it is occurring.
Step 3: Turn Off the Equipment
Once everyone has been informed that the lockout is about to take place, ensure everyone is done with their jobs, then simply power down the energy source.
Step 4: Locate and Isolate Energy Sources
Although your equipment should now be powered down, there may some residual energy remaining inside machinery.
The next step of lockout is therefore to ensure that this leftover energy is removed, which may require the use of such techniques as blocking, bleeding and venting.
The most important thing to remember here is there should be absolutely no energy left over that could potentially move a part of machinery. Residual energy could suddenly power the machinery during maintenance work, leading to accidents.
Step 5: Lock Out Switches and Energy Controls
This is one of the most important parts of the entire lockout procedure.
Energy sources must be fixed in an off position before this takes place, then the responsible person must attach a lockout device to the part of the installation that powers machinery (the energy source).
Once the lockout device is placed, one or more people can then attach clearly identifiable padlocks to it, thus firmly securing the energy source in an off position.
A tag should be also applied to the lockout, which ensures you adhere to the regulations of tagout.
Step 6: Test that it is Impossible to Activate the Energy Source
First of all, make sure nobody is near the machinery that the energy source could activate.
Once this is done, you can activate the operating controls (if possible) by pressing the operating switch. If a lockout is correctly enforced, it should be physically impossible to activate it. This process is basically to ensure that the energy source can’t operate at any point during maintenance.
Step 7: Test Circuits
There may be dangerous electrical energy left inside the machines. Have someone ensure that the electrical components of the machinery are completely de-energized, as live electrical parts can easily lead to extremely nasty electrical shocks.
Step 8: Complete the Maintenance
Once all of these procedures have been carried out, it is now acceptable to complete the work on the machinery without fear of it suddenly activating.
Step 9: Remove the Lockout
Before doing this, you must ensure that all employees working on the job are accounted for and moved away from machinery. When possible, each employee should have their own padlock to remove from the lockout, thus accounting for themselves.