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De-energization and Lockout

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Presentation on theme: "De-energization and Lockout"— Presentation transcript:

1 De-energization and Lockout
Introduce yourself and take this opportunity to explain to your audience your background and your history with this organization and others. This presentation is to help you understand the requirements for lockout of machinery and equipment. It will outline lockout rules, lockout procedures, and will help you recognize the risks of failure to lockout correctly.

2 Agenda WorkSafeBC OHS Regulations Definitions Responsibilities
Risk identification and hazard assessments

3 Agenda Lockout procedures: Lock removal and restarting
End of shift transfer Removing another worker’s lock

4 Agenda Lockout Procedures – continued Working on energized equipment
Group lockout Mobile equipment lockout

5 Training Objectives Attendees will:
Understand various terms and definitions Be familiar with WorkSafeBC Regulations Know your responsibilities By the end of this session you will: Understand the definitions of various terms used for isolation and lockout. For example, when we talk about controlling energy sources or control power, everyone will understand exactly what the terms mean. Be familiar with Part 10 of the WorkSafeBC Regulation. Understand your and others responsibilities for lockout

6 Training Objectives Attendees will - continued
Recognize situations where lockout is required Be able to conduct various lockout procedures Recognize lockout situations Understand how to implement isolation and lockout

7 WorkSafeBC Regulations
10.2 – 10.3 When lockout required 10.4 Lockout procedures 10.5 Access to energy isolating devices Using Electrical panels for lockout Regulation part 10.2 requires lockout if the unexpected start-up of equipment or the unexpected release of an energy source could cause injury. Note that there is no difference in this Regulation between operation and maintenance. Regulation part 10.3 requires lockout prior to maintenance work being done, and during normal production, as failure to lockout would cause a risk to workers. Regulation part 10.4 outlines how to lockout and the requirements for padlocks. Regulation 10.5 refers to electrical panel boxes that may have a locking door. If one of the breakers is thrown, and then the door is locked and the worker keeps the key, that can be a valid lockout. It cannot be used if locking the door would prevent someone else from locking out.

8 WorkSafeBC Regulations
10.6 Verifying lockout 10.7 Worker responsibilities 10.8 Removal of locks Regulation part 10.6 requires that someone test the equipment after it is locked out to make sure the energy source that is locked out is the one that powers that particular piece of equipment. Regulation part 10.7 lists the worker responsibilities for lockout. Regulation part 10.8 listed procedures that must be followed if someone forgets to remove their padlock at the end of the work and subsequently leaves the work premises.

9 WorkSafeBC Regulations
10.9 Group lockout procedure 10.10 Alternate procedures Regulation part 10.9 outlines the requirements for using group lockout. This is sometimes referred to as a lockout board. Regulation part 10.10 outlines procedures that must be followed if the equipment cannot be locked out. One example is in BC Hydro substations.

10 WorkSafeBC Regulations
10.11 When locks are not required 10.12 Work on energized equipment Regulation part 10.11 lists the two exceptions to the lockout requirement. The first is when there is only one worker working on the equipment and no one could throw the electrical switch without the worker seeing him or her. The second exemption refers to the ability to simply disconnect electrical cords. Regulation part 10.12 requires written procedures when troubleshooting requires the equipment to remain energized during maintenance work. You might ask: Can anyone give an example of when Regulation would come into effect? You might answer: Truing a band saw wheel in a sawmill, when the wheel must be turning in order to perform the work, or electrical troubleshooting, when an electrician is looking for the source of a fault. There are many other examples in mobile equipment.

11 Definitions Control power De-energization
The power source that activates the main energy source De-energization Procedure to disconnect and isolate equipment A relay switch or button can connect or disconnect this power source. An example of control power is the on/off switch on a radial arm saw. In the event of a short circuit, energy may still flow to the equipment or machinery. Therefore, control power cannot be used for lockout. In the case of the radial arm saw, de-energization would be accomplished by pulling the plug if it was soft wired or throwing the breaker switch if it was hard wired. A procedure to disconnect and isolate equipment or machinery from a source of energy to ensure equipment or machinery cannot move or harm workers De-energization is the first step in lockout. Once the equipment is de- energized, the decision on whether or not to lockout can be made by referring to WorkSafeBC REgulation part You might ask: Can anyone give an example where de-energization would not be followed by lockout? You might answer: Unplugging a skill saw to change the blade. Turning off the ignition in a vehicle and pocketing the key prior to changing a fan belt. (In this case true de-energization would involve disconnecting the battery.)

12 Definitions Energy Sources Electrical Mechanical
Hydraulic or Pneumatic Chemical Thermal Other sources The Regulation defines energy source as: “means any electrical, mechanical, hydraulic, pneumatic, chemical, thermal, or other source of energy of potential harm to workers.” Most people only consider the power to drive the equipment but there can be other sources of energy to consider. Here are some examples of other sources of energy: Gravity: the bed of a dump truck that can fall if the hydraulic system fails or is disconnected Spring: the return spring of an overhead garage door Hydraulic: equipment often has additional hydraulic connections Steam: may be introduced to provide heating or drying You might ask: Can anyone give an example of “back pressure”? You might answer: Disconnecting or working downstream of a valve at the bottom of a tank that is filled with liquid.

13 Definitions Energy Isolating Device
Prevents release of energy to equipment May include switches, circuit breakers, valves An energy isolating device is a device that physically prevents the transmission or release of an energy source to machinery or equipment. Typical energy-isolating devices include switches, circuit breakers, and valves. When doing maintenance work on electrically controlled equipment, workers should be aware that stop buttons on control circuits and programmable logic controllers cannot be used as energy-isolating devices. During lockout, the main power source for the machinery or equipment must be disconnected and locked out at all times.

14 Definitions Group Lockout A system to simplify multiple lockout
Note: Use this slide only if group lockouts are used. Group lockout is a system to simplify multiple lockout if several workers must work on the equipment or where there are many lockout points. A typical example of when group lockout is an advantage would be where a piece of equipment must be replaced and, because of the valving, piping and electrical connections, there might be 10 different lockout points. Rather than have each worker lock out 10 separate points, a group lockout would be performed. Two workers would lock out all of the energy sources, and then put their keys into a box, which would be locked out by all of the other workers. Another example is a water valve lockout. Because of the location of the water valve – typically in a roadway – it’s not possible to put everyone’s lock on the valve. A group lockout may be used for this purpose.

15 Definitions Hard Start
Attempting to start equipment after de-energization and lock out After the equipment has been de-energized and locked out, it is necessary to test to see whether or not the equipment has been properly de-energized. In order to do this the first person who locked out must attempt to start the machinery or equipment using the on/off button or switch. This is called a hard start.

16 Definitions Interlock A switch that prevents machinery from starting
An interlock is a device, such as a micro switch or electric eye, used to help prevent a machine from harming its operator or damaging itself by stopping the machine when tripped. They can be as sophisticated as curtains of infrared beams and photodetectors, but are often just simple switches. An interlock can prevent the locked out machine from starting when tested but it may still be able to start when someone starts working on it. This can create a very dangerous situation. A simple example is a household microwave oven. These are equipped with interlock switches which disable the magnetron if the door is opened. You might ask: Does anyone have an example of an interlock that is used in our facilities? You might answer: Interlock on the gate to a machine to crush cardboard. Thermostat on air conditioning equipment. Timers on electrical equipment such as lighting or pumps.

17 Definitions Personal Lock Lockout Unique lock issued to a worker
Use of a lock to isolate equipment The WorkSafeBC Regulation defines personal lock as: “a lock provided by the employer for use by a worker to ensure personal lockout protection such that each lock when applied is operable only by a key in the worker's possession, and by a key under the control of the supervisor or manager in charge.” [Insert how locks are issued in your organization] Locks are for lockout purposes ONLY. Each lock can be opened only by a key that is in the worker’s possession and by a key under the control of the supervisor or manager in charge. Control of keys includes a registry of locks and strict control of spare keys. Combination locks MUST NOT be used. Each personal lock must be marked or tagged to identify the person who applies it. If more than one lock is issued, the set may be keyed alike and each worker’s key is different from other worker’s keys The Regulation defines lockout as: “the use of a lock or locks to render machinery or equipment inoperable or to isolate an energy source in accordance with a written procedure;” Lockout requires written procedures. The procedures must be specific to each piece of equipment that must be locked out. There are are three basic steps to lockout: Stopping the energy flow is de-energization Applying a lockout device is locking out or isolating Attempting to start the equipment can be either a hard start or a soft start We will discuss a soft start in a minute.

18 Definitions Lockout Scissors
Allows more than one lock on a lockout point You might want to have an example of a lockout scissor to pass around. A lockout scissor is a device that allows more than one lock to be used on an energy isolating device. May switches have enough room for only one padlock. If two workers are going to work on the locked out equipment WorkSafeBC requires that the scissors be put on the switch and then both workers must apply their lock to the scissors. It is a violation of the lockout procedures to put your lock in the last available hole of the scissors. If you do that no one else can lock out. If there is only one hole left, you must provide another scissor.

19 Definitions Maintenance
Work done to keep equipment in safe operating condition Installing Repairing Cleaning Lubricating Clearing obstructions The OHS Regulation defines maintenance as: “work performed to keep machinery or equipment in a safe operating condition, including installing, repairing, cleaning, lubricating and the clearing of obstructions to the normal flow of material;” Maintenance includes such simple procedures as changing the blade on a radial arm saw in which case lockout procedures are required. Maintenance, for lockout purposes, often includes work that is done by the equipment operator.

20 Definitions Normal production Routine, repetitive work
Integral to normal use of equipment The Regulations define normal production as: “work that is routine, repetitive, and integral to the normal use of machinery or equipment for production” Remember that if a worker would be exposed to inadvertent movement or danger by the equipment during routine production, then the equipment must be locked out. The classic example is any use of Robotics or electric eye triggering mechanisms. You might ask: Does anyone have an example of normal production work where lockout might be required?  You might answer: Cleaning the grate in a sewage treatment plant or changing chlorine or ammonia bottles in a pool or arena.

21 Definitions Powered Equipment or Machinery
Equipment that uses or stores energy, and Can start unexpectedly, or Can release energy unexpectedly Powered equipment or machinery is any equipment or machinery that uses or stores energy and can start unexpectedly or release the energy unexpectedly, potentially injuring workers. With very few exceptions, the only equipment that is excluded from lockout is a hand tool. There is no requirement to lock out an axe when it is being sharpened, even though it is a dangerous tool in the wrong hands.

22 Definitions Qualified Person
Knowledgeable of the hazards and how to control them The WorkSafeBC Regulation and Act define qualified person as: “A person, knowledgeable of the hazards and the means to control them, who will de-energize equipment or machinery if the process is complicated or hazardous.” In complicated cases where a “qualified person” is required, the [Organization] maintains a list of persons who are qualified to do the isolation and de-energization.

23 Definitions Soft Start
Starting equipment from a computer control station Note: Use this slide only if it applies to your Organization. A ‘soft start’ means trying to start the equipment or machinery from a computer control station. Sometimes it is impossible to test equipment to ensure that it has been de-energized after it has been locked out. When the equipment is computer controlled, the computer may act as an interlock. In these cases it is necessary to test the equipment at the computer station.

24 Responsibilities Employer Senior Managers Managers / Supervisors
Workers Note: This slide must be customized with the actual names or job titles of the individuals who will be responsible for the different aspects of your lockout program.

25 Responsibilities Employer / Senior Management
Establish the lockout system Ensure personal locks are available Ensure written procedures are developed Ensure workers are trained The most important responsibility of this organization in the lockout program is to ensure that it is effective. An ineffective lockout program puts workers at risk. The employer is responsible for establishing the lockout system to be implemented within the worksite. Procedures for lockout must be written. Depending on the size and complexity of the operation, other aspects of the lockout system may have to be established in writing. For example, emergency lock removal and multiple point lockout. These procedures will be discussed in a few minutes.

26 Responsibilities Managers / Supervisors
All workers understand and follow procedures Workers have personal locks Other lockout equipment is available Maintain list of equipment requiring lockout Workers are trained Ensure that all workers understood and follow lockout procedures. Ensure that all workers who may be required to lock out are equipped with personal locks, each of which can only be opened by two keys. The first key is given to the worker. The second or duplicate key is kept in secure, locked storage and is accessible only by the supervisor in case the lock removal procedure is required. Other equipment may include lockout scissors and other equipment required for lockout purposes. Maintain a list of equipment requiring lockout and hazard and risk assessments for his/her area. Ensure that employees have received training in lockout procedures prior to operating the machinery or equipment. Also: Ensure that each employee and contractor engaging in work requiring lockout of energy sources understands and adheres to proper procedures. Provide and maintain necessary equipment and resources, including accident prevention signs, tags, padlocks, seals and/or other similarly effective means. Where applicable, develop operation-specific lockout procedures and make them available to workers. Ensure that procedures are developed for new or revised equipment, machinery, or operations that require the use of lockout during servicing, maintenance, or repair.

27 Responsibilities Workers Participate in lockout training
Lock out using proper procedures Ensure lockout is in place before starting work Remove personal locks when job complete Keep control of keys to personal lock All workers who work on machinery or equipment requiring lockout are responsible for: Locking out the energy-isolating device or placing a personal lock on the key-securing system in a group lockout procedure. Removing their personal locks on the completion of their work. Keeping control of the keys to personal locks throughout the duration of their work.

28 Hazard Identification and Assessment
For each piece of equipment: Complete hazard Identification checklist Complete risk assessment for each hazard Develop lockout procedures For each piece of equipment or machinery, a Hazard Identification Worksheet must be completed listing the hazards posed by inadvertent startup, inadvertent movement, or the release of energy. It must also state the type of energy that must be controlled. A Risk Assessment must then be performed on each hazard to determine whether or not the risk of injury is significant in the absence of lockout. The department manager will keep these risk assessments. The lockout procedures MUST minimize or eliminate each significant risk. If de-energization alone is required, the work procedures are documented, e.g. blocking up attachments and installing pins to lock equipment or machinery in place, or using a solid ram to hold a truck box up. If lockout is also required, the steps must be listed, as well as each of the de-energized energy control devices that must be locked out. Note: If you have time, facilitate a quick workshop using the lockout hazard identification and risk assessment worksheet which is found in the appendix to the lockout program. Using this is an example you could develop your own completed worksheet for a task that everyone is familiar with. Changing a tire on the vehicle is an example that does not have to be work-related. You can lead the group in identifying the hazards involved and the tasks to be performed. This will give the group a good idea of how the hazard identification and risk assessment is done. In Appendix B of the Lockout Program there is a worksheet that can be used to identify hazards and assess risks. The hazard identification is based on identification of different types of energy sources. There are examples of each of the types of energy. Qualified workers use the worksheets to identify the hazards of specific equipment. Once the hazards are identified, the tasks that must be performed on the equipment are listed on the worksheet. If any of those tasks pose a risk to workers the de-energization method for the equipment and that task is listed. Finally, the energy control device and lockout point for that equipment is identified. This information is used to develop the lockout procedure that is specific for that equipment.

29 Lockout Procedures Lockout Sequence De-energize Apply locks
Verify lockout A typical lockout sequence has seven steps. It may be difficult to remember all of the steps. Sometimes it helps to have a memory jogger. Note that the phrase “Drown Little Villains In Rich Red Tar” can be used to remember the seven steps. D for de-energize the equipment; L for locks; V is for verify; …Continued on next slide…

30 Lockout Procedures Lockout Sequence - continued Interlocks
Release energy sources Lock removal End of shift transfer …CONTINUED from previous slide… I is for checking interlocks; R is for release energy sources; R is for removal; T is for transfer

31 Lockout Procedures De-energize Identify the energy sources
De-energize and isolate If complicated, “qualified person” must de-energize Shut off the machinery or equipment. Use the power control device, usually the start / stop switch on the equipment or machinery, to shut it down. Ensure that all moving parts have come to a complete stop. Ensure that shutting off the equipment does not cause a hazard to other workers. Identify and de-activate the main energy-isolating device for each energy source. This procedure may require closing valves, throwing switches, pulling a lever or inserting a blank in a pipeline. There must be a written procedure that can be followed for each piece of equipment. The procedure can be posted directly on the equipment.

32 Lockout Procedures Apply locks Each worker attaches his/her own lock
Cables cannot be used for more than 4 switches Apply a personal lock to the energy-isolating device for each energy source. Ensure all parts and attachments are secured against inadvertent movement. If you do not know the lockout procedure for the equipment / machinery, contact your supervisor. If there are more than two lockout points for the equipment or machinery it must be listed on the specific lockout procedure sheet. If there is only one lockout point, it should be posted at the lockout point Each worker must apply his or her own lock. This includes any supervisor, technician, inspector or other person who may be exposed for only a brief time. Sometimes, in a motor control center, instead of locking each switch it's possible to throw the switches and feed a cable through all of the padlock holes. By putting a padlock on the end of the cable so that it cannot be pulled back through the holes, an effective lockout can be installed.

33 Lockout Procedures Verify lockout
First person to apply lock tests lockout Test from the operator’s console Disable computer controls or interlocks Attempt a soft start on computer systems The most experienced person should apply the first lock and test the equipment. Test the lockout to make sure it is effective and to verify that each energy source has been effectively locked out. Before testing, ensure all workers are in the clear and that no hazard will be created if the lockout is not effective. Try to start the equipment or machinery using the start/stop button or other power control device. Ensure that there are no interlocks upstream of the equipment or machinery that are giving a false reading at the start stop button. All residual pressure must be bled from the system. Hydraulic and pneumatic machinery may still cycle after being locked out if pressure is not bled from the system. Remember that if you are the first person to lockout the equipment or machinery, you are responsible to ensure it is safe for anyone else who locks out.

34 Lockout Procedures Interlocks
Upstream interlocks can give false reading Must be noted in written procedures Upstream interlocks can give a “false-safe” reading when testing the effectiveness of the lockout Any interlocks in the system must be noted in the written procedure. Interlocks can include computer-controlled actions or electric eye activators.

35 Lockout Procedures Release Energy Sources
Ensure all sources are released Written procedures should address this Several additional sources of energy can be present Written procedures should specify the various sources of energy to be released Note: you can review the various energy sources that might be encountered in Appendix B2 of the written program. Discuss specific examples that are found in your Organization. You can use a flipchart to brainstorm and list examples of each of the types of energy sources.

36 Lockout Procedures Lock Removal and Re-starting Remove all tools
Guards in place Notify affected employees Equipment in neutral Each worker removes his/her own lock Each worker must remove his or her OWN lock. There have been a number of instances over time where workers gave their key to someone else to remove their lock. This seems like a simple and safe shortcut at the time, however this is an unacceptable practice under any circumstances that can lead to serious injuries or death of a worker. Lock Removal and Restarting Equipment - When the work is completed: Remove all tools from the equipment or machinery. Ensure all the necessary guards are put back in place. Notify all affected employees, including responsible operators, that the lockout will be removed. Remove your lock(s). The last person to remove their personal lock must check the work area to be sure that all workers are clear of the equipment or machinery. If you forget to remove your personal lock when you leave the worksite, you will be contacted to come back and remove your lock. If you cannot be contacted, the lock removal procedure will be implemented, and you will be informed by the beginning of your next shift. This is the only situation in which someone may remove a lock other than their own.

37 Lockout Procedures End-of-Shift Transfer Orderly transfer of locks
Use to maintain lockout integrity A system for an orderly transfer of locks at the end of shift A procedure for using a departmental lock to maintain the lockout integrity If the work is not completed by the end of the shift, it is important to maintain the integrity of the lockout. The way to do this is for at least one worker going off shift to leave his or her lock on until the first worker from the next shift applies his or her lock. If a lockout is going to be maintained over a weekend or another long time period, a departmental lock can be used to maintain the integrity of the lockout. If you must leave the worksite before the job has been completed, you must remove your personal lock. If there is important information about the safety of other workers to be passed on, or if the equipment or machinery is unsafe to operate, contact your supervisor to ensure no one starts the equipment. A “Do Not Operate” tag or departmental lock must be applied to the equipment or machinery.

38 Lockout Procedures Removing Another Worker’s Lock
Supervisor attempts to contact worker Supervisor removes lock as per procedures Document steps taken – use form Guards at danger points Notify worker prior to next shift Note: The lock removal procedure is found in the written Lockout Program. The form is in Appendix E of the Lockout Program. Call your audience’s attention to the lock removal form. Go through the form step-by-step. Explain how it is used. Emphasize that locks will not be removed routinely Implement the lock removal procedures only if a lock is inadvertently left on a lockout point. The supervisor must make every effort to contact the employee whose lock is on the equipment or machinery. If the employee can be contacted, the employee must remove their lock personally, or give permission to remove their lock. If the employee cannot be contacted, the supervisor, or person in charge, may remove the lock while following these procedures: The supervisor, or person in charge, must document the steps taken to contact the employee, using the Lock Removal Form. The supervisor, or person in charge, must station guards at every danger point on the equipment or machinery prior to startup. The supervisor may now remove the lock. The supervisor takes full responsibility for any mishap as a result of starting the equipment or machinery. The supervisor must notify the worker by the start of the worker's next shift if the worker's personal lock has been removed.

39 Lockout Procedures Working On Energized Equipment
Equipment operation required during maintenance or testing Written alternative procedures required Note: this overhead is OPTIONAL and is applicable only if working on energized equipment is done in your organization. If so, use your organization's specific written procedures. Discuss and distribute the written procedures. Some maintenance work can be performed only if the equipment or machinery is running. In these cases, written alternative procedures that provide the same protection as lockout must be developed and followed. It must be ensured that power is supplied only to the part of the equipment or machinery that must have power to do the job.

40 Lockout Procedures Group Lockout Requires two qualified workers
Written checklist must be used and posted Container secured by 2 personal locks Each worker must apply personal lock Either qualified worker can remove locks Note: this overhead is OPTIONAL and is applicable only if group lockout applies. The group lockout procedure is used when a large number of control devices must be locked out at the same time. Two qualified workers are responsible for independently locking out the energy control devices using two groups of locks with each group of locks keyed separately from the other and a written checklist that lists all of the lockout points. When the lockout is complete, these two workers must secure the keys used for the locks in the container designated for this purpose. They must secure the container using their personal locks. The qualified workers will use their own, different, personal locks to secure the container. Lockout scissors may be required to allow other workers to secure the container. They must complete the checklist, sign it, and post it.   Each worker who works on the locked out equipment or machinery must apply a personal lock to the container that contains the keys. If a group lockout is in effect, ensure that the lockout procedure checklist is the right one for the job, that it is completed correctly and that the keys are in the container. Using lockout scissors, lock the key box with your personal lock. After completing the work, each worker must remove his or her personal lock from the key container. When all locks have been removed, the two qualified workers will remove their personal locks from the container. Once the keys have been released from the container the system is no longer locked out. Either of the two qualified workers can now remove all of the locks from the system.

41 Lockout Procedures Mobile Equipment Lockout
Mobile equipment must be locked out Use ignition key and lockbox Multiple lockout procedure may be necessary Disconnect battery Mobile equipment which is removed from service using information tags which state “Do not Operate” is not considered to be locked out. When lockout is required for maintenance work on mobile equipment, the mechanic doing the work must lock out the equipment and keep possession of the key to the equipment. If there are two or more workers working on the equipment a multiple lockout system must be used whereby the key to the equipment, e.g. either the ignition key or the steering wheel lock key, will be placed in a lockable box and both workers will place their personal locks on the box. A multi lock hasp / scissors may be used if applicable For equipment that does not require a key, the service switch (commonly known as the night switch) must be disconnected and access to the switch must be closed and locked or otherwise rendered inoperable, i.e. disconnect the battery. For minor repairs on mobile equipment, e.g. lights or electrical system, where the service person is always in or directly by the vehicle and is able to directly control the start up / ignition switch while the work is being done: Remove the ignition key from the ignition. The ignition key must be kept in the possession of the technician working on the equipment. There should be no other ignition key readily available. Place a "Do Not Start/Operate" sign on the steering wheel. If servicing must be done with the equipment operating, a written safe procedure must be developed and followed.

42 Lockout Procedures Individual lockout procedures
Equipment-specific procedures Lockout checklist Lock removal form Note: You can use this part of the presentation to introduce and discuss specific procedures that are used within your organization. Have copies available for distribution.

43 Summary Lockout procedures protect YOU Follow lockout procedures
Never attempt lockout without training Control your lock and key Understand all procedures Report unsafe acts and conditions

44 Summary Review of topics WorkSafeBC Regulation Responsibilities
Hazard identification and risk assessments Lockout procedures During this session we have discussed: The regulatory requirements for lockout, Responsibilities for lockout Hazard identification and risk assessments Lockout procedures including: General lockout Interlocks End of shift transfer Removing another worker’s lock Working on energized equipment Group lockout Mobile Equipment lockout

45 Questions We are about to complete a quiz to make sure everyone has understood the presentation. Before we do that does anyone have any questions? Handout the quiz.

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