LoTo(To) stands for Lockout Tagout (TryOut) ELECTRICAL SAFETY

 

LoTo(To)

LoTo(To) stands for Lockout Tagout (TryOut) and protects an employee by preventing others from using equipment or the switch on the machine during maintenance work or during troubleshooting. It also offers protection against the release of (residual) energy in the equipment or machine.

How does it work?

All power sources are turned off/closed and locked in the off position. This could be due to, for example, the locking of an isolation switch or a valve. The employee locks the isolation switch/valve with his own personal padlock (Lockout) so that he/she has control over the energy source. In addition, a label (Tagout) placed on the padlock to warn others who is responsible for this particular padlock. Because the padlock is personal, no one else can remove someone else's padlock. Therefore can no one accidentally turns on the equipment.

Before the employee goes to the next step, he tests whether the closed maintenance switch/valve is still switched on can be (Tryout). This may of course not be the case.

LoTo(To) is therefore not only there for electrical work but also for mechanical engineering activities. The latter is not always known to everyone.

Lockout, Tagout and Tryout further explained

LOCKOUT

Switch off all possible hazardous energy at isolation points (mains switch, valves, etc.)

Secure all isolation points (isolation switch, shut-off valves, etc.) with a locking system so that they cannot be switched on early and without authorization.

TAGOUT

Applying warning tags to (service switch, valves, etc) for reference.

Tagout does not offer the same guarantee as lockout! Therefore, use all items of the LoTo!

TRYOUT

Make sure that no residual energy is present. Pay particular attention to: mechanical parts of the machine (can it still make its “stroke”)?, is there still energy in the pipeline (hot/chemical liquid or gas)?

Risks: What could happen?

Employees who carry out maintenance or repairs on machines or on/in electrical or mechanical installations do risky work. They open the installation or the machines, parts thereof, which exposes them to other hazards than the employees who operate and/or use the machines or installations.

After all for the operators/users were shielded from the dangers.

For example, employees who carry out maintenance or repairs may come into contact with:

• moving parts
• live parts
• a hazardous substance

The hazards that can occur are also referred to as 'energy sources'. To prevent injuries and damage to health, the machine or the installation part must be closed prior to the work, (this is also called 'isolating').

All of these overlying risks can result in serious health damage or even death!

What are dangerous energy sources

The following types of energy sources can be distinguished when working on installations/machines:

• Mechanical: moving parts (e.g. conveyor belt, gears, agitator) or materials (e.g. ejected particles, flowing product)
• Electrical (e.g. electrical voltage, static electricity)
• Gravity (e.g. being buried in product)
• Thermal: exposure to high or low temperatures (e.g. radiation, chemical reactions, steam, electrical resistance)
• Liquids and gases under pressure (e.g. in hydraulic systems, pneumatic systems, gas tanks, pressure vessels, steam pipes)
• Chemical: exposure to hazardous substances
• Radiation: exposure to ionizing radiation, non-ionizing radiation, electromagnetic fields
• Biological: exposure to bacteria, fungi and viruses

Follow the steps below of the LoTo(To) procedure to safely enable and disable the machine and/or installation (part).

Release (secure)

STEP	EXPLANATION
1	PERMISSION Request permission from the machine/installation manager, preferably via the work permit, to release the installation.
2	SWITCHING AND DISCONNECTING (Attention! only isolation switch then limited in work) After switching and disconnecting (in accordance with Operating manual/instruction), the installation must be completely separated from the power sources.
3	PROTECT AGAINST RE-ENABLING Fit a lock or dummy to each switch and/or valve. Attach the 'Don't Switch' label with name, phone number, department and date. On the other side you indicate the reason for switching off.
4	CHECK Show that there is no voltage with a suitable measuring instrument according to the applicable method (first duspol, then prove that there is no voltage, then duspol again) Show that there is no longer any pressure in the part of the installation where you are going to work Show that there is no more residual product in the pipework Show that the temperature has cooled down sufficiently
5	EARTHING AND SHORT CIRCUIT In E-installations (≥400 Volt) make provisions against earthing and/or short circuit as extra protection against voltage.
6	SHIELD ACTIVE PARTS Adjacent active/conductive parts which mayby come under voltage during work; shield with insulating tape or with deposits.
7	TEST If applicable, test whether the installation has actually been released by performing an operating operation.

Gate Valve Lockout

Switching on (recommissioning)

STEP	EXPLANATION
1	CHECK Check whether the work is ready. Check that employees have been informed and that tools and materials have been removed from the installation.
2	PERMISSION Request permission from the machine/installation manager to switch on the machine/installation.
3	REMOVE PROTECTIONS Remove any grounding and short-circuiting devices. Remove all locks and dummies. Remove the 'Don't Switch' label.
4	TO CHECK Carry out a commissioning inspection, in accordance with the Maintenance and Operation Regulations of the relevant machine/installation.
5	SWITCH Switch on the machine/installation according to the applicable procedure in the Operating Manual. Sign off the 'Don't Switch' label.
6	READY FOR USE Give the machine/installation manager (and operators) a sign that the installation is ready for use.

https://www.wermac.org/safety/safety_what_is_lockout_tagout.html

Six Steps of LOTO Safety & Lockout/Tagout Procedures

A lockout/tagout procedure should include the following six steps:

1.      Preparation

2.      Shutdown

3.      Isolation

4.      Lockout/tagout

5.      Stored energy check

6.      Isolation verification

Let’s look at each of these steps of LOTO safety more closely in the sections below.

Lockout/Tagout Step 1: Preparation

The first step of locking and tagging out equipment for service and maintenance is to prepare.

During the preparation phase, the authorized employee must investigate and gain a complete understanding of all types of hazardous energy that might be controlled. In addition, it’s important to identify the specific hazards and of course means for controlling that energy.

Use this Guide to Types of Hazardous Energy to investigate this issue more fully.

Lockout/Tagout Step 2: Shut Down

With planning complete, the actual process of powering down and locking out machines begins.

At this point, it’s time to shut down the machine or equipment that will be serviced or maintained.

Another important part of this step is to inform any employee affected by the shutdown, even if they won’t play a role in the service or maintenance.

Lockout/Tagout Step 3: Isolation

The next step of the lockout/tagout procedure is to isolate the machine or equipment from any source of energy.

This may mean any number of things, such as turning off power at a breaker or shutting a valve.

Lockout/Tagout Step 4: Lockout/Tagout

With the machine or equipment isolated from its energy source the next step of lockout/tagout is to actually lock and tag out the machine. It’s fair to say that this entire six-step process takes its name from this step.

During this step, the authorized employee will attach lockout and/or tagout devices to each energy-isolating device. The point is to apply the lockout device on the energy-isolating device in a way so it says in the “safe” position and cannot be moved to the unsafe position except  by the person performing the lockout.

Tagout refers to applying a tag on the device as well. This tag includes the name of the person who performed the lockout and additional information.

 

Lockout/Tagout Step 5: Stored Energy Check

Even after the energy source has been disconnected, in step 3  of the lockout safety process, and the machine has been locked out, in step 4, that doesn’t entirely guarantee that there’s no hazardous energy still stored within the machine or that it’s safe to perform maintenance.

At this time, it’s important to look for any hazardous energy that’s been “stored” within the machine, or any “residual” energy. During this phase, any potentially hazardous stored or residual energy must be relieved, disconnected, restrained, or made non-hazardous in some other way.

Lockout/Tagout Step 6: Isolation Verification

This last step is all about making sure.

Yes, you’ve shut down the machines, isolated them from their source of power, locked them out, and checked for hazardous stored energy. But now’s the time to double-check that you did it all right and it’s now safe to work on the machine or equipment.

At this point, an authorized employee verifies the machine has been properly isolated and de-energized.

The example images shown above are all from one of our two online Lockout-Tagout training courses. We have one for Affected Employees and a second for Authorized Employees. Click those links to learn more and see a sample about each online lockout course, and/or watch the short sample video below from our Lockout Training for Authorized Employees course.

REFFFERENCE 

:https://www.vectorsolutions.com/resources/blogs/loto-safety-6-steps-of-lockout-tagout/