Electricity kills! Doesn’t it? even if your experience as an electrical engineer or electrician is at the top, you should never mess with electricity.
Electrical isolation is one of the most important tasks in our work. It should be done only by qualified persons to ensure a safe working and incidents-free workplace.
I always double-check the isolation myself before starting any maintenance or repair work.
Table of Contents
What is electrical isolation (Lockout Tagout)?
Electrical isolation, also known as lockout ta gout or LOTO, is the process of isolating electrical power, putting a lockout safety device, labeling the isolation with a tagout, and making sure no other source of electrical energy can feed the equipment under isolation, to secure the equipment and the workers.
Electrical equipment has power, this power comes from the electrical power source, this source may be a generator, electrical transformer, or even an electrical panel through an electrical cable called a feeder.
Now, assuming we have an electrical motor and we need to replace an AC fuse in the motor control panel, we should make proper electrical isolation for the panel and the power source of the motor before replacing the fuse.
We apply LOTO as a safety precaution before any work inside the panel of the motor. We should make sure no power source is feeding the panel, on the other hand, we should make sure no one will reconnect power accidentally. This can be achieved only by LOTO.
Isolating electrical power procedure
You should go through a well-prepared power isolation procedure to ensure that everyone on the job is safe.
- check the power source feeding your panel (note that some applications have more than one power source)
- announce any person who may work in the location during your work
- make a proper work permit
- prepare isolation certificate
- isolate power from main source(you may need to open a circuit breaker, stop generator, isolate transformer or any other needed isolation)
- use the LOTO system (I will discuss it later in this article)
- check power using an AVO meter after performing electrical isolation
What is the LOTO system?
LOTO stands for Lock Out and Tagout, which is a simple but important system to make sure that no one else will de-isolate power while you are still working on, it or when it’s not safe to connect electrical power for any reason.
LOTO is simple, as below:
- Lock out the power source with a safety padlock.
- Tagout with a safety isolation label, and write on it the isolation reason, time and who isolates the equipment.
We apply a powerful isolation LOTO system in my workplace. We have an isolation station, which has the following items:
- Safety isolation padlocks.
- Isolation accessories.
- Tagout labels.
- And the most important one is the Isolation Tracking File.
The isolation tracking file has all the data about any isolation process, the employee who performed the isolation, the padlock serial number, the isolated equipment, the isolation date, and the purpose of the isolation.
We also keep the keys in this station. When we are about to remove an isolation we look at the file, and give the key to the person who will remove it, and the most important part is that we record these data.
Tracking the isolation is essential and prevents any accidental isolation removal.
What is the difference between lockout and tagout?
Lockout refers to the placing of an electronic lock on a device which prevents the release of energy.
Tagout is the act of using an identification tag on a switch or any other device that is isolated to warn others against starting this piece of equipment.
Locking out is meant to stop machinery or equipment’s sudden start-up or activation during maintenance and service operations. Tagout is only employed with lockout, except when it is not possible.
While being serviced or maintained, equipment should be locked out. Accidents involving machinery that is being fixed but is not locked out frequently result in significant injuries such as amputations, fractures, and even death.
When repairing or modifying machinery, it is critical to lock out and tag electricity at its source to guarantee that power does not reach the machinery.
What is the procedure for the removal of Lockout and Tagout?
Before removing lockout/tagout devices and restoring power, the authorized employees must undertake the following procedures:
- The work area must first be inspected to verify that all things like tools or spare parts have been removed and all machine or equipment components are in ready status.
- The work area must then be verified to confirm that all employees have been properly positioned or have cleared the area.
- Before starting the equipment, all impacted personnel must be told that the lockout or tagout devices have been removed.
- The employee who applied the device must remove each lockout or tagout device from the energy-isolating device.
What are main LOTO equipment?
LOTO system needs two main things, the first is something to lock out the electrical equipment, like a safety padlock.
The second is a caution and information tag to inform others not to connect the equipment, this should contain information like the isolation person, date, lock number, and reason for isolation.
An electrical isolation archive should contain all data about each isolation process of any equipment, this archive is a good way to check equipment performance.
Where do we need electrical isolation?
All electrical work fields need isolation procedures because it’s the best way to ensure that everyone in the working area is safe.
All electrical equipment and machines may require LOTO during maintenance. Some times when equipment is out of service with potential hazards if some one energized it you should apply LOTO.
What are the benefits of using Lockout tagout?
Lockout/Tagout (LOTO) is a set of protocols that ensure that equipment has been shut off, is not operational, and is de-energized. This permits maintenance and repairs on equipment to be carried out without risk.
Power isolation is not only electrical power isolation but also any type of power such as mechanical, chemical, or any power source which could be dangerous if not controlled and isolated.
The following are the benefits of employing lockout Tagout:
- Workers are protected against dangers and accidents.
- It prevents equipment, machine, and workplace damage while reducing downtime.
- It demonstrates senior management’s care for the safety of their employees.
- Reduces the possibility of damage if machines are accidentally activated by mistake.
- Making workplace safety a top priority fosters confidence and trust in employees.
- It minimizes the danger of injury or death from hazardous energy releases such as steam blasts, corrosive chemicals, and electrical arc flashes.
- Ensures that no one connects power accidentally.
- Ensures that everyone on the site knows that it is not safe to connect or operate the equipment.
- Provides data about the isolation person, date, and reason of isolation.
- Isolation history archive is a good way to enhance equipment working and maintenance.
What is the primary method of electrical isolation?
Separating an electrical installation by disconnecting it from its main source is only one aspect of the secure isolation process.
There are additional steps to take, like obtaining authorization for the task before the actual work and checking the installation’s voltage afterward.
The following are the steps involved in the safe electrical isolation method:
- Get the authorization to begin work on the installation (this depends on the nature of work you’re doing and the type of work you’ll be doing in a commercial or domestic location).
- Find what the source(s) of the supply is.
- Check your voltage detector or test lamp to ensure it works correctly.
- You can isolate the supply by disconnecting the supply from the mains.
- After disconnecting again check with your tester or test lamp to ensure that the main supply is cut off and there is no voltage.
- Secure the isolation or “lock out” the isolation with a safety padlock, which will prevent any interference.
- Install clear warning signs that clearly show that the area is now isolated.
- Try to start the equipment while the LOTO is applied to make sure it’s fully secured.
I have written a detailed article about LOTO on my other safety frenzy site you can read it here.
Who should remove a lockout/tagout?
Only the individual who applied the Lockout Tagout devices is allowed to remove them from energy isolating equipment.
Employee locks should not be removed without the knowledge. As a general rule, the Lockout Tagout device should be removed by the employee himself/herself.
When can another employee remove the lockout device?
When the authorized employee who applied the lockout or tagout device is unavailable to remove it, the device may be removed by another employee at the employer’s discretion, provided that specific procedures and training for such removal have been developed, documented, and incorporated into the employer’s energy control program [29 CFR 1910.147(e)(3)].
Can I use tagout in place of lockout?
Tagout devices may be used instead of lockout devices only if :
- The application of the lockout is not possible for any reason.
- The lockout is applicable but the tagout program provides a protection level comparable to a lockout program.
When employing Tagout-only systems, the employer must take extra precautions to guarantee that this technique is as secure as physical locks.
These actions might be removing a control relay from the control circuit of the equipment to make sure it can’t be started.
Employees must have a suitable training program on the tagout-only system to make sure they all will be safe while applying this tagout.
Why are LOTO locks different colors?
Padlocks can be color coded to differentiate the department, equipment groups or severity of the danger involving the equipment.
Different colors of LOTO locks identify which person locks the machinery or equipment; locks are color-coded in the following way:
- Red: The authorized worker locks out the equipment with the red locks.
- Yellow: Before start working on the equipment, the affected worker installs his yellow lock on the Multi locked tool.
- Orange: Before working on the equipment, the Affected worker from the contractor sets his orange lock on the multi-locked hasp.
- Purple: When a lockout will continue to the other shift, the authorized worker places a transition purple lock on the lockbox.
Can lockout locks be keyed alike?
No, lockout locks can not be keyed alike; referencing OSHA’s 1910.147 requirements, no employee should be able to unlock a lock that has been applied by someone else.
As a result, keyed similar locks from the same set should never be provided to several employees at the same time.
Any locks used must have only a single key. Master-keyed locks used for lockout/tagout can be confusing. Never use a multi-key or master key for the purpose of replacing the lost key lock.
Does lockout/tagout only apply to electrical energy?
Lockout/Tagout does not apply only to electrical energy. All shapes of energy may require Lockout Tagout to control the hazard of the energy during maintenance or other conditions when running the equipment or the machine is a hazard and could cause injury to employees.
Hazardous energy should properly be controlled. This energy may be electrical, mechanical, hydraulic, pneumatic, chemical, or thermal.
For more detailed electrical safety and hazrd read my article on my safetyfrenzy site.
What is the first step of performing a lockout procedure?
Preparation is the first step in locking and tagging out equipment for servicing and maintenance.
The preparation phase is all about understanding everything there is to know about the harmful energy contained in the equipment. You should know the energy type and sources and how to isolate it.
The authorized personnel must examine and get a comprehensive grasp of all forms of dangerous energy that may be managed during the preparation phase.
Furthermore, it is critical to identify particular threats and strategies for regulating that energy.
What are the requirements for tagout devices?
Tagout devices are special important labels, the data on this tagout is as important as the safety of workers, so the tagout device should be:
- Capable of withstanding the isolated environment. OSHA [29 CFR 1910.147(c)(5)(ii)(A)(1)].
- Non-releasable without the use of excessive force.
- Easy to attach to the lockout.
- Not deteriorate when used in corrosive environments.
- Singularly identified
- Have one format.
- Warn against hazardous conditions
I have written a full detailed article about electrical safety checklist for home and workplace on my other site “SAFETYFRENZY” you can find it here.
Who are affected employees in a lockout/tagout?
Workers who are authorized to work on the isolated equipment, on which servicing or maintenance is being performed under lockout, or work in the area of the equipment are affected persons.
Affected employees are responsible for providing help as needed, helping the authorized employee ensure correct shutdown and identification of isolation areas.
They also ensure that do not attempt to start locked or tagged out equipment or machinery and are responsible for the care of Do not attempt to remove or tamper with locks or tags for whatever reason.
On the other hand, the authorized person who will isolate the equipment should make sure all affected persons are aware of the maintenance and isolation work duration before starting.
Do affected employees need LOTO training?
Affected employees do require training. They should be aware of the goal and use of energy control techniques like:
- The rationale behind Hazardous energy control procedures and the reasons they’re used.
- Restarting or re-energizing equipment or equipment that is restricted or locked out is prohibited.
- The risks associated with their work when they are performed in lock/out or tag/out conditions.
- Understand the critical importance of not start up or using locked-out equipment.
How often is LOTO training required?
As per OSHS recommendation, lockout/tagout training for all authorized, affected and other employees is necessary. And retraining must be provided whenever there is a change in job assignments, machines, equipment, energy control procedures, work location, or work nature that presents a new hazard.
LOTO training is very necessary; that’s why authorized employees must have knowledge about:
- how to recognize energy sources.
- how to measure this energy, like how to measure voltage.
- how to isolate and lockout this energy.
Affected and other employee training should help them to:
- know when it is necessary to use energy lockout/tagout
- Why lockout is being used
- why it’s critical not to try to operate a machine with lockout/tagout?
Does lockout/tagout training expire?
Lockout/tagout training certification does not have an expiration date, however there are specified retraining requirements.
As Per OSHA 1910.147(c)(7)(iii)(A): Re-training shall be recommended for all authorized anytime their job assignments change, machinery, equipment, or processes that provide a new danger change, or energy control techniques change.
What are the exceptions to the lockout/tagout requirements?
Some servicing operations performed during normal production applying the Lockout/Tagout standard. This exception is referred to as the minor servicing exception.
The Lockout/Tagout standard criteria for the minor servicing exception are Routine, Repetitive and Integral. i.e. regular course of procedure, regularly repeated and essential to the production.
Alternative measures must be applied to provide effective protection from hazardous energy during these minor servicing exceptions.
These measures must be under the exclusive control of the employee performing the minor servicing. Accepted measures such as:
- Control switches.
- Specially designed tools.
- Local disconnects
These measures must provide safety for the employee during the performing the minor servicing task without unexpected energy release or starting the equipment.