Cheater bar

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A cheater bar or cheater pipe is an improvised breaker bar made from a length of pipe and a wrench (spanner).

Contents 1 Primary Use 2 Other uses 3 Rules and regulations 4 Problems with cheater bars 5 Industrial safety problems 6 Radiological safety 7 Nuclear power plant safety 8 Safety Culture 9 Notes

[edit] Primary Use

Cheater bars are usually used to break loose screws, bolts, and other fasteners that are difficult to remove with a ratchet or wrench alone. When the handle of a wrench or ratchet is inserted into a cheater bar, the additional length makes it possible to generate higher torque with the same amount of force being applied.

This is so because: torque = force * length

A cheater bar is sometimes called a pipe extension or an extension pipe.

[edit] Other uses

A cheater bar can also be used to apply more torque to a valve stem that will not rotate using the amount of torque that can be applied without the cheater bar.

[edit] Rules and regulations

Some organizations forbid their use. For example, NASA proscribes:

"Use the approved tool for the job. Makeshift arrangements such as the use of a screwdriver as a chisel, a pair of pliers as a wrench, a wrench as a hammer, or overloading a wrench by using a pipe extension (cheater bar) on the handle are not to be employed." ^[1]

[edit] Problems with cheater bars

The use of a cheater bar introduces new hazards into a job that is usually conducted without needing a cheater bar. The Job Hazard Analysis (JHA) is apparently incomplete if it does not address the additional hazards introduced by using the cheater bar.

The use of a cheater bar often applies more torque than the designer of the valve (or fastener) provided for in the design. In this case the cheater bar exerts torque outside the design operating envelope. In this case, it is a condition outside the design basis of the engineered component.

The component needing the cheater bar for operation may be degraded or inoperable.

A cheater bar is one example of a 'workaround.' A workaround is a situation in which a worker cannot perform the desired action in the manner intended in the design and must do something else in order to accomplish the task.

Use of a cheater bar indicates that there is a condition adverse to quality (CAQ) in the component being worked. Using the cheater bar just gets around the CAQ; it does not correct it.

[edit] Industrial safety problems

Problems in using such bars include:

1. If the component frees suddenly the worker can become a projectile that is propelled into whatever is in the "line-of-fire." This could (and has) resulted in falls, impacts, punctures, and other injuries.
2. The cheater bar itself can become part of a de-facto catapult with the worker in the line-of-fire.^[2]
3. If the over-torquing results in the failure of any of the items in the jury rig the fragments can injure workers in the line-of-fire.^[3]
4. The use of the cheater bar can result in component damage that can, in turn, harm workers.^[4]

[edit] Radiological safety

A radiological safety problem with using cheater bars in a radiation field is that use of the cheater bar requires a much longer exposure of the worker in the radiation field. This raises issue of the extent to which the exposure is ALARA (As Low As Reasonably Achievable).

[edit] Nuclear power plant safety

In a nuclear power plant the use of cheater bars raises other safety issues. For example, if use of the cheater bars has not been captured in the Corrective Action Program, it raises the issue of the adequacy of the "measures established to assure that conditions adverse to quality are promptly identified and corrected".

Also, in nuclear power plants, the use of cheater bars in situations involving off-normal conditions raises the issue of the allowed (or assumed)time to accomplish that action.

Again, in nuclear power plants, the use of cheater bars raises issues about the effectiveness of the reporting and use of Operating Experience(OE) from the plant itself and other plants.

When cheater bars are used on components whose operation is taken credit for in the probabilistic risk assessment (PRA) it raises the question of the validity of the PRA under the new conditions.

When the cheater bars have been used for some time it raises the issue of the effectiveness of root cause analysis (RCA) in support of problem identification and correction.

[edit] Safety Culture

When the use of cheater bars is "normal" it raises questions about the safety culture and the safety conscious work environment (SCWE).

The safety culture issues include the extent to which this is an example of "normalizing deviance".

When cheater bars have been used and the use has not been identified as a potential safety issue it raises other questions about the robustness of the safety culture.

The use of cheater bars can be a tip-of-the-iceberg window into the safety culture of organizations that allow the use of cheater bars without procedures, controls, and training.

[edit] Notes

1. ^ http://server-mpo.arc.nasa.gov/Services/Proc/ProcDocs/APG1700.1-R/Chap%2014.pdf
2. ^ http://www.eh.doe.gov/paa/oesummary/oesummary2005/oe2005-03.pdf
3. ^ http://www.nrm.qld.gov.au/mines/petroleum/pdf/safety_alert015.pdf
4. ^ http://pepei.pennnet.com/Articles/Article_Display.cfm?Section=Articles&ARTICLE_ID=240117&VERSION_NUM=2&p=6