OSHA COMPLIANCE ADVISORY

“Raised Cab” LockOut Procedures for Apparatus Operators

Cal/OSHA requires that employees whose job duties include performing repairs or maintenance on equipment be familiar with methods to “Lock Out” potentially hazardous forms of energy. While energized equipment poses the most obvious danger, many forms of energy – including the force of gravity – exist in the workplace. The following information has been prepared to alert Department personnel of a recent fatality, outlining required safety measuresfor performingany work under the raised cab of fire apparatus.

Incident:

Last month, a mechanic at Johnson Power Systems in Riverside, California was working under the raised cab of a fire truck which fell, pinning him against the truck’s tire. The incident was not witnessed by other employees, who later discovered him. Efforts to revive him were unsuccessful.

Analysis:

Hydraulic systems, such as that which elevatesthe cab, can fail or be deactivated during repair or maintenance operations, allowing the cab to fall - with disastrous results. To address this, Department procedures requirethat while work is being performed under the cab, ‘Lock Out’ devices be used to secure the cab in place.

This incidentalso points out the importance of the ‘buddy system’ in avoiding tragedy. Whether it’s a fire scene or working under the raised cab of an apparatus, Department procedures require that employees work as a team when in potentially hazardous situations. In regards to the incident at Johnson Power, if the mechanic had had assistance – someone to “watch his back” - his death might have been prevented.

Procedure:

Department personnel are required to ensure safe operations for “raised cab” work by engaging the manufacturers’ safety measures installed by apparatus’ manufacturersand ensuring they are secure before beginning work. (For detailed information, see reverse.) Additional precautions, such as situational awareness and the “buddy system,” can completely address the issue of worker safety.

Securing the cab and reviewing the hydraulic systems are top priority. Leaking hydraulic cylinders, damaged or loose fittings, and broken lines or components can cause the cab to fall, with disastrous results.

Field Operations

Engineers and other apparatus operators are required to inspect apparatus and to perform routine maintenance, requiring that they put their head and upper body “into the lion’s mouth.” In doing so, they are exposed to serious hazards which must be addressed with fail-proof measures:

  • Factory-installed cab restraints are to be used – and checked to ensure that they have been engaged.
  • Apparatus operators are to employ the “buddy system” when working under the raised cab of apparatus. With such help, the Riverside incident might have been prevented.
  • The cab must be raised to the fully upright position before beginning work. In the recent incident, this was not done, reducing the mechanic’s reaction time when the cab fell.
  • Place ‘Cab Jack’ controller in a safe location to prevent activation. This was also a contributing factor in the recent incident: The controller was found under the cab, where it might have been accidently triggered.

Cab Restraints

Methods vary for securing the cab of fire apparatus in the raised position, but all manufacturers have developed mechanisms to ensure safe operations while working under the raised cab.

KME (1993, 1995, 1998)

Cab is raised using controller for truck’s “Cab Jack” hydraulic system (pictured). When the cab reaches maximum height, the restraints must be manually engaged by turningand pulling handle (inset) which lowers the restraining bar in place. When repairs are complete,the restraints are retracted according to the instructions (orange and black label) posted inside the compartment for the Cab Jack controls.

KME (2006)

Similar to previous models, but with second locking arm must be lowered into place by hand. When repairs are complete, the manual arm must be raised and secured.

Other Methods

Other brands of fire apparatus require different measures to secure the cab in an upright position. One method requires that “collars” be installed on the hydraulic pistons, which prohibit the cab from falling.

Restraining collars are heavy-walled pipe, split lengthwise (inset) and secured around the piston (see photo) by raising the cab to its full height and installed on both hydraulic pistons. The restraints prevent the cylinders from retracting, allowing work to be safely performed beneath the raised cab.

Cab restraints ensure your safety and must be used. Conditions can change in an instant. Don’t forget that this is Earthquake Country!

Contact the Department Safety Office for additional information at (323) 881-3091.