A Well Designed Lockout Tag – the Keys to a Successful Lockout / Tagout Procedure

Two linemen for a California utility, one with over 30 years of experience and the other in training, were assigned to perform a routine oil test on a transformer. In the midst of the operation, the trainee accidentally trips over a ledge and spills hot oil onto the leg of his older colleague. The older colleague reaches out and makes a connection between a circuit and the grounded vault enclosure. He dies instantly. The trainee survives, but is badly burned in the ensuing explosion. No one will ever know if a better lock-out/tag-out program could have stopped the accident. Inadequate personal protective equipment, poor worker training and equipment design, and non-conformance with established safe work policies could all be contributing factors. But, there is little question that locks, tags and signs can be your last line of defense against a fatal accident.

In spite of tremendous investments in safety programs and equipment, tragic accidents continue to occur. This article describes how a well designed program of safety tags, locks and personalized training can help save lives.

Lockout / Tagout Procedure
Lockout / Tagout Procedure
Lockout / Tagout Procedure
Lockout / Tagout Procedure
Lock-Out/Tag-Out Regulations
Lock-Out/Tag-Out, or “LOTO”, is the second most cited OSHA violation. The primary regulations are OSHA §1910.147 Lock-Out/Tag-Out, §1910.269 for Electric Power Generation, Transmission and Distribution and §1910.268 for Telecommunications. These rules require that all energy sources be turned off and either locked out or tagged out while service or maintenance work is being performed. By protecting the worker from accidental release of energy (electrical shock, mechanical action, heat, etc.), this rule is saving hundreds of lives every year. With larger fines, criminal liability and aggressive enforcement by OSHA, more companies are taking heed and enforcing this crucial safety system.

Engage Employees to Make LOTO Training More Effective

The trick with any training is getting workers to “buy in” to your program. Safety procedures are not set in stone. To be effective, you need to continually update support materials. Then, find case histories that are relevant to your workplace. Use a video to illustrate the cause of accidents that are common in your work environment. Understand that it may take longer to follow the lock-out steps and to complete the tag that to make the actual repair. Training must emphasize that there are no short-cuts.

Effectively enforcing your new procedures is paramount. OSHA writes in the preamble to 1910.147 about tagout enforcement:

“It is the fourth element, discipline, which appears to be the most critical to the success of these programs; the companies with effective tagout programs apply various types of disciplinary action to both supervisors and employees who violate the tagout procedures.”

A common line on Lock-Out tags is “You will be fired if you remove this tag without authorization.” Allowing violations to occur without penalties is inviting apathy and will foster disrespect for your safety program.

Use of Tags vs. Locks

Although tags are generally used with a lock, many companies still use tags alone. This approach works only when the company’s training and tracking program is established and effective. In writing the OSHA 1910.147 rules, the issue of tags versus locks was debated extensively. Ultimately, OSHA decided that lock-out was the preferred and safer way to ensure that equipment remains de-energized. However, tags alone can be used when an energy-isolating device is incapable of being locked out. Tags are sufficient when the employer can “demonstrate that the tag out program will provide a level of safety equivalent to that obtained by using a lockout program” 1910.147 (a)(3)(c)(3).

This loose approach is fraught with pitfalls. Many users acknowledge that tags are much easier and faster to use, and more likely to be implemented than a program relying only on locks. There are occasions when using a lock is impractical and even more dangerous than a tag. In developing your own program, you must honestly assess the effectiveness of your training, your written procedures and the capabilities of your workforce.

Expect More from Your Tag

Companies are rapidly integrating their work-order procedures with their lock-out tag systems. Detailed instructions, information on control points and even simple diagrams are being printed on the lock-out tags. After all, a tag is only part of the workflow involved in a work or maintenance request. Many companies find it useful to attach a stub from the actual tag to the work papers. The stub is often used to indicate that the work has been completed and traces back to the individual performing the work. Laser Printable LOTO Tags Similarly, a paper carbon or NCR copy of the tag can provide this record.

Finally, software programs can now be used to store detailed LOTO instructions and then tags can be printed on laser and desk-top thermal printers. Highly readable laser-printed tags help reduce the problems of handwritten instructions, which are frequently difficult to read. Oftentimes, the personnel writing a tag are confronted with the need to make hundreds of tags. Importantly, they are often performing this task under time restraints, such as during a storm-related emergency. These are situations during which time and accuracy are of critical importance. Laser printed tags help eliminate the human error. Now that laser printers have dropped below the $200 threshold, they are a remarkably affordable solution.

LOTO Procedures and Continuing Failures
Most utilities already have well-established written procedures with clear goals, specific procedural steps for energized projects, an inventory of potential hazards, group lock-out programs and descriptions of the manager’s auditing and control responsibilities. The outside plant environment is unique; in order to have an effective program in place, a LOTO procedure must address the following trends in this environment:
  • Expanding Diversity of Workforce. Construction firms, utilities and contractors are struggling with higher turnover and more entry-level trainees than ever before. Many utilities respond by hiring outside contractors, bringing yet another level of complexity and uncertainty concerning the lines of authority.

  • Technological Acceleration. Today’s outside plant is far more sophisticated than the one we knew 10 years ago. For example, activation of a circuit may occur at a control center that is miles away from the actual maintenance work. The work may overlap several shifts and oftentimes involve teams of electricians. Many of the current LOTO training programs are built around the needs of a manufacturing environment and directed to simple nearby repair. The “one-person, one-lock” scenario suitable for cleaning a simple machine is unworkable when you have dozens of control points. Similarly, asking CATV employees, to endure a training session on machine guarding is inappropriate.

  • De-Regulation. There is greater pressure than ever to increase worker productivity. Get the linemen out of the classroom and back out on the job as quickly as possible is a common philosophy.

  • Greater reliance on Tag-Out and Tag Durability.Unlike general industry, utilities are more likely to rely upon tags alone. And unlike manufacturing environments, safety tags used in outside plant must be able to withstand rain, sunlight and wind.

A plant’s written program can only go so far. The annual viewing of the 20 minute “LOTO” video is not enough. Problems remain in the execution of the training program and the quality of the tag itself.

The tag is often protecting someone’s life. Make sure that your message is clear and direct. The primary message of the tag should give the necessary action to take (for example, “Do Not Operate”). Make this primary message large and bold. Other common messages are: Do Not Connect, Do Not Energize , Do Not Open, Do Not Reclose, Do Not Start, Keep Your Hands Off, Hold Tag, Locked Out and My Life Is On the Line.

The use of symbols is also favored by ANSI tag standards. A symbol conveys the danger quickly and powerfully, even to workers who do not read English well or cannot read small print.

Lock-out symbols Lock-out symbols

Many plants even add a photograph to the tag. A digital camera can take a picture and then instantly translate it to an electronic form. With such a record, you can translate your personnel photos for inclusion in the LOTO procedures and the tags. A personalized lock-out tag not only helps you find someone, especially when you have so many contractors on a project, but helps convey the singular immediacy of the danger.

Lockout / Tagout Procedure

Tags Must be Durable

The tags themselves can be upgraded from paper to plastic. Investment in safeguarding equipment and training will be lost if the lock-out tag is not durable. The tag, after all, is the last line of defense against a potentially lethal mistake.

Self Lam Tags

Plastic tags resist oil, sunlight and oil attack. In contrast, paper tags mildew, rip and become illegible in the rain. Putting a paper tag into a plastic bag can be even worse — the bag creates the greenhouse conditions that can accelerate a tag’s deterioration. Tags should have a 3/8” hole to accommodate the width of a lock shank. OSHA’s guidelines define that the tagout device shall have “an unlocking strength of no less than 50 pounds” 1910.147 §(c )(5)(C )(2).

Tags need to be easily removable at the end of the work cycle. Old, redundant tags can corrupt the integrity of your program. Having a small slot or perforation allows personnel to rip it in half and remove it when the job is complete.

Attaching and then Discarding a Tag

Historically, there have been many ways to attach a tag: cotton string, nylon cords, wire, ball chain and ties. OSHA 1910.147 is quite clear though: “the employer is required to provide a means of tagout device attachment having the general design and basic characteristics of being at least equivalent to a one-piece, all environment-tolerant nylon cable tie” OSHA 1910.147(c)(5)(ii)(C)(1). When asked to rule on the suitability of using a cord, an OSHA officer writes, “Neither the cords nor the tag appear to be all environment-tolerant, that is, if wet, neither would hold up.”

Also, remember that tags should be temporary. The integrity of your LOTO program depends on old tags being discarded or logged out. Old, redundant tags can corrupt the integrity of your program. Some users even request that a perforated section of the tag so that the tag stub can be sent back to the office to record a completed job.

Don’t let your Tag be a Wallflower

Above all, make the tag conspicuous. Remember that the tag is guarding someone’s life and must stand out. Fluorescent colors or a striped border can be used to help the tag stand out.

The ANSI standard for lockout and safety tags , Z535, shifts the design away from the traditional OSHA designs. The simpler Danger header using the signal alert triangle is emphasized (see top), instead of the traditional Danger design using the red and white oval shapes (see bottom).

ANSI Header Classic Header

Make tags large enough to read. A blocking tag must be filled out completely. Leaving too little room to complete and will frustrates the operator. In a hurry, he will often sloppily complete the tag. The next worker, who is then deciding which switch to energize may, for example, be too vain to admit that he needs bifocals. This is a recipe for disaster. Larger tags allow the Danger header to be sized big enough to meet the OSHA 1910.145 requirement; the signal word should be "readable at a distance of five feet or such greater distance as warranted by the hazard.”

Lastly, it is important not to forget the back of the tag. The best tags give instructions on the back of the tag on how to follow your LOTO procedures.


Many LOTO programs have not fulfilled their promise. Employees too often feel like bystanders to an arbitrary management procedure. Training programs tailored to your work environment will help change these attitudes. Durable, easy to fill-out and understand tags that are integrated with your work procedures reinforce the importance of your LOTO program and empower the employee. Both initiatives signal a fundamental respect for the employee’s safety and that means fewer needless accidents.

Lockout Stations


  • OSHA 1910.147, Control of Hazardous Energy Source (Lock-Out/Tag-Out), 1989
  • OSHA 1910.269, Electric Power Generation, Transmission and Distribution; Electrical Protective Equipment, 1994
  • OSHA 1910.145, Specifications for Accident Prevention Signs and Tags, 1971.
  • ANSI Z244.1, For Personnel Protection- Lockout/Tagout of Energy Sources- Minimum Safety Requirements.
  • ANSI Z535.5, American National Standards. Accident Prevention Tags (for Temporary Hazards).