Safe Operation & Maintenance of Automated Equipment
When working in these well-equipped research facilities, we encounter problems in two main categories: noise and the inherent dangers of the machinery. This month’s column discusses Lockout/ Tagout, the procedures used to isolate and de-energize complex machinery so that repairs or maintenance can be performed safely.
Lockout/Tagout measures are taken to prevent the release of unwanted or stored hazardous energy. If we fail to develop and follow a good Lockout/Tagout program, the result leads to some of the most grisly, and often fatal, accidents in the workplace. One recent example that has been in the news lately involves a student who got her hair tangled in a lathe while working alone late at night. Can you imagine the horrible discovery?
The latest data from the Bureau of Labor Statistics shows that during the past three years (2004 to 2006) fatal incidents involving being struck by or coming into contact with equipment ranked third behind falls and highway incidents.1 In addition, in 2006 alone these accidents accounted for 17 percent of the total.1 The sad thing is that every one of these incidents could have been easily prevented.
What do we mean by Lockout/Tagout?
Lockout/Tagout is the name we give to the program that complies with the OSHA standard for the control of hazardous energy, i.e., 29CFR1910.147.2 Briefly, this regulation applies to any employer whose employees must service or maintain machines where unexpected start-up, energization, or release of stored energy could cause injury. It addresses all sources of energy, including mechanical, electrical, thermal, hydraulic, pneumatic, and chemical. The principle is simple and easily understood: lockout (or tagout) the energy source or equipment prior to working on it. However, due to the different types of energy and complexity of the equipment and controls, a well-thought-out and detailed procedure is best.
Lockout (the OSHA-required method unless this is infeasible) refers to placing an actual lock or physical block on the circuit breaker, switch, or other energy control. Devices exist on the market for most configurations. Tagout allows a tag to be placed on equipment or controls that cannot be locked out. Exceptions are permitted where the hazardous energy can be completely controlled by the employee performing the maintenance or service. Examples include a single electrical plug or valve right at the machine. Special procedures are also permissible where continuity of operations is essential or shutdown of the system impractical, such as with pressurized steam, water, or gas distribution lines.
The fundamental rules for a good Lockout/Tagout program are “one lock—one employee” and “you put it on—you take it off.” Sharing of locks or passing of keys should never occur, even when changing shifts. Another cardinal rule is “Test it before working on it.” Even if all procedures have been followed and locks or tags placed, employees should “throw the switch” before beginning work to ensure that unexpected start-up does not happen. This will eliminate injuries from potential stored energy sources such as batteries, capacitors, and pneumatics.
A comprehensive Lockout/Tagout program is methodically detailed. Tunnel and rack washers, conveyors, and other automated equipment have the potential to injure employees in lots of different ways due to the many forms of hazardous energy. In addition, modern automated equipment more than likely will contain more than one form of hazardous energy. The following five-point program will help get your Lockout/Tagout procedures up to speed in a hurry:
- Set clear responsibilities and procedures. Your written program should establish responsibilities for all employees regardless of job assignment or whether they ever hang a tag or lock. The program should also provide detailed procedures to ensure that proper sequences are followed and all energy sources are neutralized. It is important to have a supervisor on each shift who has overall responsibility and authority for the Lockout/Tagout program. This is critical if equipment might remain locked out through a shift change to ensure that turnover is complete and safe. Remember our cardinal rules: one lock, one employee, one key, and don’t forget to test it.
- Training. All employees are affected and have some responsibility under lockout/tagout. The amount of training will vary based on job responsibilities. At a minimum all employees should recognize the inherent equipment hazards and whether proper lockout procedures are being followed. Include hands-on as well as classroom training and written testing to demonstrate competence. Use a multimedia approach encompassing lectures, computer-based information, videos and demonstrations to keep it interesting and ensure that you are reaching the entire audience.
- Second independent checks. This follows our cardinal rule of “Test it before working on it.” Having a second independent set of eyes look everything over is never a bad idea, especially in facilities with multiple units or identical pieces of equipment. Ideally, the second look is conducted by someone other than those involved in originally setting the lockout/tagout, someone who knows the specific equipment. A second check verifies proper and complete lockout, avoids confusion, and often finds problems or something that was overlooked.
- Document and follow up on violations. As we have seen, short-cutting on lockout/tagout can lead to serious injury or death. Employees must understand the importance of the program and the consequences of not following the procedures. This is one area where we cannot afford any mistakes. Hopefully any oversights are caught by the second check, documented, corrected, and used in the next training session. Never tolerate persistent or willful violations and investigate all reports of such violations promptly. Follow up swiftly with corrective actions or reprimands as appropriate.
- Audit, audit, audit. Regular audits help identify problems with procedures or gaps in the program before they become serious or result in injury. Audits are essential to ensure that employees retain knowledge and are competent to perform their duties, and audits also identify who needs retraining and when. Perform program audits weekly or at least monthly. Ensure that audits are written and include reviews of procedures and logs as well as physical inspections of active lockout/tagout projects. Determine the reasons and implement corrective actions and/or training for any discrepancies found as soon as possible.
The Safety Guys welcome your comments and questions. You can contact them at firstname.lastname@example.org. Until next time, “Stay Alert” and remember “Safety First!”
1. Bureau of Labor Statistics, “Census of Fatal Occupational Injuries,” US Department of Labor. 2008. (http://www.bls.gov/iif/oshwc/cfoi/cfch0005.pdf)
2. OSHA, “The control of hazardous energy,” 29CFR1910.147. 1989 (http://www.osha.gov/pls/oshaweb/owadisp.show_ document?p_table=STANDARDS&p_id=9804)