Introduction
Every year, in different factories, thousands of accidents occurred worldwide related to machineries and equipment and result severe injury and consequences as fatal and permanent disability. This occurred because of lack of knowledge and procedural awarnes while work on live machine or electrical system. To overcome or get rid of this problem, a safe practice of Lock out and tag out to be introduced to prevent such severe accident and injury.
What does actually means to Lock Out and Tag Out ?
Lock out and Tag out is a Technique and Practice used when person working on electrical installation or electric plant and machineries. Name itself describe the objective and moto of LOTO system. it is safety procedure or engineering controls with intention that dangerous machine and equipment must properly shuts off and it is not able to start until unless the maintenance work or repair work completed. By implementing this procedure as safety control, we ensure the “ZERO ENERGY STATE” of equipment or instrument or dagerous machnaries under consideration.
How does Lock Out and Tag out play a crucial role in Safety?
As we know the repairing and Maintenace work are continuing at different places and on different machineries and equipment. The Power supply of most of machineries are connected from a centralized control room or Machine Control center. When a maintenance worker servicing the machine, he could face so many hazards while work on e.g.. Elerick shock, sudden startup of machine, sudden operation of rotating parts of machine. These hazards if realize and convert in accident then it could results severe consequences like fatal case, amputation, electric shock, electrocution, crushing of body parts etc.,. Lock out and tag Out Prevent us from these hazards and save the life of person working.
A well established LOTO procedure Play a vital role in safety and below are benefit of LOTO system:
- Gives warning about machine engagement.
- Give information who is responsible to operate the machine under consideration,
- it isolate the operating energy form system .
- It is a good method of physical isolation of machine from source of energy.
What are the key element of LO-TO-TO System ?
- Mechanical and electrical Isolation:- Isolate the machine or equpiment from source of energy supply.
- Lock -out :- Lock the energy supply sources as ON or OFF condition , cut the supply to machine under consideration
- Tag-out :- Fix a warning tag at suitable location at energy sources , machine or Operation side to avoid unintetional startup of machine or equipment under consideration
- Try Out :- After isolation to ensure and verify whether or not energy sources became de-energized condition, try to operate the machine and it should not operate.
How can one implement practically LOTO Procedure at their workplace?
For practical implementation of Lock out and Tag out procedure , following step to be taken:-
- Identification of energy sources: first of all identify all the energy sources which are associated to macjine or equipement or instrument under consideration for repair, maintenance or modification . Energy could be in the form of electrical power, pressure, temperature, kinnetic energy , stored energy, spring contracton, hydraulic pressure, air pressure , hazardous material or any others thing which have a potential to damage or injury if thsese are not released before start the work.
- Identification of componant or element of system having above energy: – Secodn task is to identify the all parts or componant having above energy , it could be valve, Pipe, Line , electrical parts, spring, switch, capacitor, motor, rotatory parts etc.
- Isolation or De-energization:- This is very crucial step of LOTO Procedure , in this steps we have to isolate the system or element under repair or maintenance , from sources of energy . Isolation could be done as mechanical isolation of all the connection physically and blind it, electrical isolation by power cut , fuse removal or cable disconnection to machine, bleed and drain all the material from pipe, valve etc., Depressurization by venting the pressure inside present , release the stored eneregy in the form of pneumatic , hydraulic or any potential energy etc.
- Lock out the Main Sources of Energy with Lock: To Prevent the intentional supply of the machine or equipment, main sources of energy to be locked with key special or individual lock designed for MCB, ELCB, ON OFF switch, Puch button switch, Handle, Valve etc. After completion of locking step , the system to be locked with key padlock and key handover to authorized person.
- Fix a warning or caution Tag or Tag out: – After De-energization of system pr locked out , A tag to be hang or attached or fixed at various vulnerable locations to aware or to prevent the unintentional start up of machineries and equipment. The tag may contain soem various cautionary note as “Do not operate ” “Men at work ” “Do not Power ON ” “Machine under Repair or maintenance” “Do not ON OFF the switch except authorized person” etc.
- Try Out :- This is alst step of LOTOTO procedure , in this step we intentionally supply the Enery to the equipemnt by ON or OFF the switch, By openeing the valve, press the push buttons, or checking the realy for power existance to ensure that the system is compleletly de-energized and there are no chance of flow of energy while work. this is doen just before start the work and in front of or in Presence of person who is responsible for execution of work. While doing so , the system shall not enetgized , if system get energized then, Check repeat the back step and find out the root casue , why did system get energized and remove the loop holes.
How can one effectively manage the LOTOTO Procedure?
If someone wants the to manage the effectively the LOTOTO Procedure, Follow the below Step: –
- Make a comprehensive Procedure as per Requirement.
- Add the LOTOTO Procedure requirement in Existing Permit-To -work system or Separate Permit .
- Periodic Training of Procedure or ON the Job Practical Training to be given to concerns Person.
- LOTO Procedure to be add in Induction Training for special group of Employees
- Define the Roles and Responsibilities of the different level of employee