• An antiquated box: Notice no area to place a lock to prevent entryelectrical box image by steve dimitriou from Fotolia.com
  
  In an industrial setting, failure to communicate when power to a machine is about to be turned on or off could cause injury or death. Because of this, the Occupational Safety and Health Administration has established safety mandates on procedures to turn the power on or off and locking a disconnect box (the main on-off switch) into the "Off" position. OSHA requires that companies develop standard procedures and has also develop specific rules for lockouts and tagouts.
  
  

Isolating the Energy Source

• All equipment and machinery must have a means of being isolated from the energy source, according to OSHA rules. A disconnect box, which is a main "on-off" switch, must be designed so when the handle is in the "off" position, it can be locked into place with a padlock, a wedge, or self-locking fastener.
  
  

Lockout Tag

• After the disconnect box is in the "off" position and locked, a tag must be placed with the lock. Each tag must include specific information under Section 1910.147 of OSHA rules, including the name of the person who placed the lock must be written on the tag. The tag must have at least one of these phrases: "Do Not Start," "Do Not Open," "Do Not Close," "Do Not Energize," or "Do Not Operate." or similar phrases indicating the circuit must not be re-energized. As a matter of convenience but not an OSHA requirement, the fastest means of contacting the person who placed the lock is usually written on the tag as well. This can be a cell phone number, or the area where the person can be found.
  
  

Tag Out

• A tagout is similar to a lockout, except than a disposable tag is used instead of a lock. According to OSHA, the device must be attachable by hand and self-locking. It can only be released if a force of at least 50 pounds is applied. The tag must must be removable with a tool, but yet still be sufficiently strong to resist removing by hand. All OSHA other mandates are the same for tagout as well as lockout.
  
  

All Clear De-Energizing Safety Check

• Before a circuit is de-energized, the responsible party must conduct an all-clear safety check, according to OSHA regulations. Many companies assign a group of people as safety officers to do this. This is to ensure all personnel working in the affected area understand that the circuit is about to be de-energized. For example, if an all-clear check was not performed, a crane could be in mid-lift when the power to it is disconnected. If the crane does not have safety brakes, then the load could drop suddenly. All personnel must understand the circuit is about to be de-energized, and ample time must be allowed to take the necessary steps to ensure safe power shutdown.
  
  

All Clear Re-Energizing Safety check

• After the electrical work is performed and before a lock is removed from a disconnect, the responsible person must conduct an all-clear re-energizing safety check on the entire affected system. Ample time must be allowed for all personnel to position themselves in a proper area of safety.
  
  

Re-energizing the Circuit

• After the all-clear re-energizing safety check, OSHA states that all personnel are made aware that the circuit will be re-energized. The padlock is removed, and the handle of the main disconnect is moved to the "on" position. At this point the lockout procedure is finished, and normal work can resume.
  
  

Other Applications of Lock Out

• Electrical disconnect boxes are not the only place lockout procedures are used. Other uses include shutoff valves in steam lines, shutoffs in hydraulic and oil lines, and gas equipment valves. The safety procedures, however, are all the same, such as informing personnel that the affected area will be de-energized.
  
  

Personnel Training

• OSHA further states that personnel must be trained on what a lockout / tagout means. This training can be done at safety meetings, or during associate orientation.