Safety Management Systems PDF

Safety Management Systems • Chapter 14 OBJECTIVE 5 Explain the purpose of equipment lookout, describe lookout devices, and describe a typical equipment lookout procedure. EQUIPMENT LOOKOUT CAUTION Information on equipment lookout is based on information available from the British Columbia OH&S Reg...

Safety Management Systems • Chapter 14 OBJECTIVE 5 Explain the purpose of equipment lookout, describe lookout devices, and describe a typical equipment lookout procedure. EQUIPMENT LOOKOUT CAUTION Information on equipment lookout is based on information available from the British Columbia OH&S Regulation. This information is presented as an example only and should not be construed as exact or applicable to all jurisdictions. Nor should the wording be accepted as the exact wording in the BC OH&S Regulation. Equipment lookout is a system of locks and tags that secure devices that prevent hazardous energy from release. The control devices that are secured by locks include the main disconnect switches, circuit breakers, valves, and clutches. Hazardous energy is any energy source (electric, compressed gas, steam, hydraulic energy, a moving part, or an elevated object) that could release or move and injure a worker. If there is the potential for an unexpected energization or startup of machinery or equipment, or the unexpected release of an energy source that could cause injury, the energy source must be isolated and effectively controlled. Equipment lockout is required when machinery or equipment is shut down for maintenance. No maintenance work may be done until the following conditions are met: a) All parts and attachments are secured against inadvertent movement. b) The hazards are effectively controlled where the work will expose the workers to energy sources. c) The energy isolating devices are locked out. Figure 2 shows an example of a typical lockout station that is used in the industry. The lockout station includes a series of locks, multiple tags that read do not operate," and multiple hasps that are used in an equipment or process lookout. The keys from the locks that are used to complete the lockout (as well as any unused locks) are placed into a lockout box. A designated operations or safety lock with a do not operate" tag and hasp is then attached to the box to ensure the equipment lockout keys cannot be accessed. The key from the designated lock that is attached to the box is then held for safekeeping by operations or safety personnel. 3rd Class Edition 3 • Part A2 727 ?& Chapter 14 • Safety Management Systems Figure 2 - Typical Lookout Station (SocoXbreed/Shutterstock) A typical portable lookout box is pictured in Figure 3. The lookout box in Figure 3 would be positioned near the work being done so workers can attach their personal locks before starting the work. Equipment lockout systems have various levels of control to ensure the safety of all workers performing work on the de-energized and locked out piece of equipment, machinery, or process. 728 3rd Class Edition 3 • Part A2 Safety Management Systems • Chapter 14 ^ Figure 3 - Typical Portable Lookout Box Lookout Procedures When a lockout of energy isolating devices is required, the devices must be secured in the safe position using locks. The devices are secured in accordance with procedures that are made available to all workers who are required to work on the machinery or equipment. The employer must ensure that each worker required to lock out has ready access to sufficient personal locks to implement the required lookout procedure. Personal locks are assigned to a specific person, meaning only that person has the keys for that lock. Combination locks must not be used for lockout. Each personal lock must be marked or tagged to identify the person applying it. Provisions must be implemented for shift or personnel changes and must include the orderly transfer-of-control of locked out energy isolating devices between outgoing andincoming workers. If the use of a personal lock is not practical for lockout, other effective means may be used to secure an energy isolating device in the safe position. An example of an alternate lockout device may be a metal cable seal with a unique identifier on it. 3rd Class Edition 3 • Part A2 729 Chapter 14 • Safety Management Systems Rotating Machinery The purpose ofde-energization and lockout is to prevent the release of an energy source that could activate moving parts on equipment or machinery. If these moving parts could potentially cause injury, the energy source must be isolated and effectively controlled. Any source of motive power that could potentially move rotating machinery must be secured after the rotating machinery is shut down and before beginning the isolation and lookout of the rotating machinery. Access to Energy Isolating Devices When an energy isolating device is locked out, the lock must not prevent access to other energy isolating devices of adjacent machinery or equipment. For example, if one valve is locked closed with a chain or cable arrangement, it cannot interfere with the movement of adjacent valves. Checking Locked Out Equipment Effective means of verifying lookout must be provided and used. Before commencing work, a worker must verify that all energy sources are effectively locked out. For example, a motor start button may be pushed to verify the power has been shut off. Bleed valves may be opened to verify lack of pressure in piping. Worker Responsibilities Each worker who works on machinery or equipment requiring lookout is responsible for the following: • Locking out the energy isolating devices before starting work, except as provided in group lockout procedures • Removing personal locks on the completion of his or her work • Maintaining immediate control of the key(s) to personal locks throughout the duration of the work Removal of Locks A personal lock must only be removed by the worker who installed it. If this is not possible, the matter must be referred to the supervisor or manager in charge. This person is responsible for its removal. The supervisor or manager in charge must do the following: • Make every reasonable effort to contact the worker who installed the lock. • Ensure that the machinery or equipment can be operated safely before removing the lock. • Ensure that the worker has been notified at the start of their next shift that their personal lock has been removed since their previous shift. Group Lookout Procedures If a large number of workers are working on machinery or equipment where a large number of energy isolating devices must be locked out, a group lockout procedure that meets the requirements may be used. Lookout procedures vary from one workplace to another. The worker must know and understand the lockout procedure at the workplace where they are employed, and must follow that procedure exactly. A violation of lookout procedures is serious and can result in disciplinary action. 730 3rd Class Edition 3 • Part A2 Safety Management Systems • Chapter 14 LOCKOUT DEVICES Lockout devices are devices that will isolate the source of danger from the worker. Locks are attached to control devices, or to a lockbox location, which will effectively keep any person from operating the equipment or exposing the source of danger until the locks are removed. Valves must be closed and locked in the closed position with chains, or with specially constructed lockout devices designed to keep that particular type of valve from being opened before the lock is removed. For example, special lockout devices are made for ball valves and gate valves. Lockout hasps or cleats are designed for electrical circuit breakers, switches, and electrical (plug) type cords. Figure 4 illustrates an example of a special lockout device designed for a valve. Figure 4 - Lookout Device for a Valve TYPICAL LOCKOUT PROCEDURE A common task that would need a lockout procedure is the repacking of a leaking pump. When repacking a centrifugal pump driven by an electric motor, the following basic lockout procedure can be used as a guideline: 1. Shut down the pump according to operating procedures. 2. Open the motor electrical breaker and lock it in the open position. Some workplaces require the electrician to perform this procedure. In this case, the electrician and the worker must both put a personal lock on the hasp attached to the breaker. 3. Confirm the electrical breaker lockout by trying to start the pump using the start/stop switch. The pump should not start since there should be no electrical power to the pump motor. 4. Close the discharge and suction valves. 5. Lock both valves in the closed position. 6. Open the drain valves between the suction and discharge valves and the pump. This will drain off any fluid pressure at the pump. If available, the drain valve and vent valve on the pump could be opened as well. Confirm there is no pressure in the pump. Lock or tag the drain and vent valves in the open position as per the lookout procedure. 7. If applicable, isolation valves for the gland seal water must be closed and locked in the closed position. 8. Complete the lockout procedure to ensure the pump is safe, and issue the work permit. 3rd Class Edition 3 • Part A2 731 Chapter 14 • Safety Management Systems A lookout procedure is generally viewed as the most reliable way to protect a worker from hazardous energy because the system is reduced to a zero energy state. A zero energy state describes a condition in which the machine, piece of equipment, vessel, tool, or electrical installation is incapable of spontaneous or unexpected action. In this state, the equipment in question is also incapable of releasing spontaneous kinetic or potential energy. A zero energy state is not accomplished by simply turning off a machine and removing the keys. A zero energy state ensures there is no residual energy left for the machine to utilize even when it is turned off. The confirmation of a zero energy state is another level of protection for the workers from any unintentional movement, unexpected energization, or release of stored energy. Proving the zero energy state involves a procedure with a more rigorous and thorough approach to ensure full de-energization of the machine, piece of equipment, vessel, tool, or electrical installation, even before starting a lockout. The following is an example of the procedure used to prepare a pump for maintenance and ensure a zero energy state condition before beginning the lockout. Steps to safely shut down a 1 A pump to a zero energy state: 1. Shut down 1A pump 2. Place J-O-R (jog-off-remote) switch to the "off" position 3. Electrician de-energize pump motor in the MCC 4. Bump test from DCS 5. Bump test local start/stop switch 6. Close 12" discharge block valve 7. Close upstream 2 warm up line block valve 8. Close downstream 2 warm up line block valve 9. Open 3/4 drain valve in between the warm up line isolation valves 10. Close 16" suction block valve 11. Open first 3/4 pump casing drain valve 12. Open second 3/4 pump casing drain valve 13. Open third 3/4 pump casing drain valve 14. Open inboard 3/4" pump casing vent valve 15. Open centre 3/4" pump casing vent valve 16. Open outboard 3/4 pump casing vent valve 17. Open 3/4 drain on pump suction piping 18. Open 3/4" drain on pump discharge piping 19. Close 1" upstream glycol supply valve to seal water coolers 20. Close 1 downstream glycol supply valve to seal water coolers 21. Close 3/4 inboard seal water cooler glycol outlet isolation valve 22. Close 3/4 outboard seal water cooler glycol outlet isolation valve 23. Close 1 common pump seal water cooler glycol outlet isolation valve End of procedure: The pump is now at zero energy state and ready for lockout/tagout. 732 3rd Class Edition 3 • Part A2