Why do we perform lockout? Well, quite simply, it is to maintain control of an energy source, and to stop machinery from being switched on while essential maintenance and service is being carried out on that particular piece of machinery.
In order to perform this procedure, it is of the utmost importance that employers study the rules and regulations of the Occupational Health and Safety Administration (OSHA) which give extensive advice about the ‘Application of Control’ of lockout/tagout.
The section below outlines each of the OSHA regulations about application of control as well as a description of what each means. The following entries from OSHA can be found inside the Federal Register, The Control of Hazardous Energy (lockout/tagout) – 1910.147. Specific sections are outlined below.
The first section states:
“The established procedures for the application of energy control (the lockout or tagout procedures) shall cover the following elements and actions and shall be done in the following sequence:” (Section D)
In short, that means you need to adhere to the procedure outlined here by OSHA and follow the correct control application.
Shutdown Preparation
Before any shutdown goes ahead, it is extremely important to prepare for the shutdown by the means of communication and determination. Under OSHA’s rules and regulations, this section is defined as:
“Before an authorized or affected employee turns off a machine or equipment, the authorized employee shall have knowledge of the type and magnitude of the energy, the hazards of the energy to be controlled, and the method or means to control the energy.” (Section D, 1)
In other words, the employees involved within an energy control program must be aware of what a machine runs on energy wise, the potential hazards involved with that machinery (including stored energy parts) and the way that they must perform lockout/tagout, which may include the supply of any relevant equipment.
Machine or Equipment Shutdown
By referencing the shutdown procedures outlined in an energy control program for a particular piece of equipment, authorised personnel can begin the shutdown of a piece of equipment or machinery.
It is also important during this process to make sure that the shutdown doesn’t present any hazards to any employees, and where possible all employees should be moved away from machinery before proceeding and the shutdown should be performed only once rigorous checks have been completed.
OSHA describes this as:
“The machine or equipment shall be turned off or shut down using the procedures established for the machine or equipment. An orderly shutdown must be utilized to avoid any additional or increased hazard(s) to employees as a result of the equipment stoppage.” (Section D, 2)
Machine or Equipment Isolation
The equipment used to lockout an energy source must be applicable to the particular type of energy source and must be of adequate quality to prevent activation. This means, for example, that you would use a ball valve lockout to lockout a ball valve, or use something such as a an MCB lockout on a circuit breaker.
This section basically tells you that equipment must be used to isolate, and is defined by OSHA as:
“All energy isolating devices that are needed to control the energy to the machine or equipment shall be physically located and operated in such a manner as to isolate the machine or equipment from the energy source(s)”. (Section D, 3)
Lockout/Tagout Device Application
OSHA’s rules and regulations centred on the application of actual equipment are extremely extensive, and it is important that you follow them all exactly to the tee to make sure your energy control program is as legal and as safe as possible.
Authorised Employees
First and foremost, “Lockout or tagout devices shall be affixed to each energy isolating device by authorized employees.” (Section D, 4, I)
By doing this, this ensures that during the procedure everyone always knows who exactly is responsible for the application and removal of lockout. This can either be one designated individual, or multiple employees can be used to apply lockout padlocks to a secure isolation point, with each person responsible for their own lock. If this is the case, there should still be a designated individual who is in charge of the entire procedure and is responsible for the safety of fellow employees.
Application of Devices
As we said earlier, the importance of lockout/tagout is to prevent energy sources from being switched on, thus preventing danger.
To do this, authorised employees use lockout/tagout devices, and OSHA has a few rules and regulations regarding the use of this equipment.
Firstly, lockout devices:
“Lockout devices, where used, shall be affixed in a manner that will hold the energy isolating devices in a ‘safe’ or ‘off’ position.” (Section D, 4, II)
Next, tagout devices:
“Tagout devices, where used, shall be affixed in such a manner as will clearly indicate that the operation or movement or energy isolating from the ‘safe’ or ‘off’ position is prohibited.” (Section D, 4, III)
In other words, the lockout device must be totally secured and the energy source shouldn’t be movable, while the tag applied should clearly indicate to anyone that the lockout is enforced and should be under any circumstances removed until designated by the responsible person.
The next section of the guide is in reference to utilising tagout instead of lockout devices, which is possible but only if it provides the same level of protection as lockout would.
The section states:
“Where tagout devices are used with energy isolating devices designed with the same capability of being locked, the tag attachment shall be fastened at the same point at which the lock would have been attached.” (Section D, 4, III, A)
If it completely impossible to attach a tag to the correct isolation point, OSHA states:
“Where a tag cannot be affixed directly to the energy isolating device, the tag shall be located as close as safely possible to the device, in a position that will be immediately obvious to anyone attempting to operate the device.” (Section D, 4, III, B)
Stored Energy
Although energy is generally distributed through a fixed point of activiation, there are also many applications where stored energy (present in many forms) can present a huge hazard to employees.
For more information on stored energy itself, visit this blog.
OSHA states that:
“Following the application of lockout or tagout devices to energy isolating devices, all potentially hazardous stored or residual energy shall be relieved, disconnected, restrained, and otherwise rendered safe.” (Section D, 5, I)
It is of the utmost importance that this is done before any maintenance is carried out – not doing so results in countless accidents every year and it essential that this easily overlooked section of the procedure is correctly followed and implemented.
OSHA says:
“If there is the possibly of reaccumulation of stored energy to a hazardous level, verification of isolation shall be continued until the servicing or maintenance is completed, or until the possibility of such an accumulation no longer exists.” (Section D, 5, II)
This means that if stored energy can suddenly reappear, there must be steps taken to isolate this immediately during maintenance. This could be in the form of a responsible person siphoning away excess energy using a lever, or alternatively it is best to make sure that the stored energy cannot reaccumulate in any way and perform extensive verifications before maintenance work proceeds.
This leads into the next section, which is all about verification.
Verification of Isolation
The final step of the application procedure is the verification process, which should be as extensive as possible. It is also important during this step to keep logs of everything, and that the responsible person should check that every energy source – including stored energy – is completely isolated and it is impossible for it to be reenergised until the lockout/tagout devices are removed from the isolation point.
OSHA states:
“Prior to starting work on machines or equipment that have been locked out or tagged out, the authorised employee shall verify that isolation and deenergization of the machine or equipment have been accomplished.” (Section D, 6)
