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Horns, Backup Alarms, and Automatic Warning Devices

30 CFR 56.14132 and 57.14132

30 CFR 77.410 and 77.1605

 

56.14132 Horns and backup alarms
57.14132 Horns and backup alarms for surface equipment

(a) Manually-operated horns or other audible warning devices provided on self-propelled mobile equipment as a safety feature shall be maintained in functional condition.

(b)(1) When the operator has an obstructed view to the rear, self-propelled mobile equipment shall have

(b)(1)(i) An automatic reverse-activated signal alarm;

(b)(1)(ii) A wheel-mounted bell alarm which sounds at least once for each three feet of reverse movement;

(b)(1)(iii) A discriminating backup alarm that covers the area of obstructed view; or

(b)(1)(iv) An observer to signal when it is safe to back up.

(b)(2) Alarms shall be audible above the surrounding noise level.

(b)(3) An automatic reverse-activated strobe light may be used at night in lieu of an audible reverse alarm.

(c) This standard does not apply to rail equipment.

 

MSHA policy can be found here: 56/57.14132

 

77.410 Mobile equipment; automatic warning devices

(a) Mobile equipment such as front-end loaders, forklifts, tractors, graders, and trucks, except pickup trucks with an unobstructed rear view, shall be equipped with a warning device that--

(1) Gives an audible alarm when the equipment is put in reverse; or

(2) Uses infrared light, ultrasonic waves, radar, or other effective devices to detect objects or persons at the rear of the equipment, and sounds an audible alarm when a person or object is detected. This type of discriminating warning device shall--

(a)(2)(i) Have a sensing area of a sufficient size that would allow endangered persons adequate time to get out of the danger zone.

(a)(2)(ii) Give audible and visual alarms inside the operator's compartment and a audible alarm outside of the operator's compartment when a person or object is detected in the sensing area; and

(a)(2)(iii) When the equipment is put in reverse, activate and give a one-time audible and visual alarm inside the operator's compartment and a one-time audible alarm outside the operator's compartment.

(b) Alarms shall be audible above the surrounding noise levels.

(c) Warning devices shall be maintained in functional condition.

(d) An automatic reverse-activated strobe light may be substituted for an audible alarm when mobile equipment is operated at night.

MSHA policy can be found here: 77.410

 

77.1605(d) Loading and haulage equipment; installations
(d) Mobile equipment shall be provided with audible warning devices. Lights shall be provided on both ends when required.

 

There is no MSHA policy for this standard.

 

These standards apply to surface (metal and nonmetal and coal) and underground (coal) self-propelled mobile equipment.  They do not apply to rail equipment.

 

Issues to Consider in Determining Compliance:

        Was the self-propelled equipment operated on the surface area of a mine?

        Was a manually operated horn provided on this equipment?

        Does the surface mobile equipment have an obstructed view to the rear (metal and nonmetal)?

»      If yes, was one of the following provided:

Automatic backup alarm; or

Wheel mounted bell alarm (metal and nonmetal); or

Discriminating back-up alarm; or

An observer

        Does mobile equipment such as front-end loaders, forklifts, tractors, graders, and trucks, except pickup trucks with an unobstructed rear view, have a warning device that (coal):

»      Gives an audible alarm when the equipment is put in reverse; or

»      Uses infrared light, ultrasonic waves, radar, or other effective devices to detect objects or persons at the rear of the equipment and sounds an audible alarm when a person or object is detected.

v     Does this type of discriminating warning device:

»         Have a sensing area of a sufficient size that would allow endangered persons adequate time to get out of the danger zone?

»         Give audible and visual alarms inside the operator's compartment and an audible alarm outside of the operator's compartment when a person or object is detected in the sensing area?

»         Activate and give a one-time audible and visual alarm inside the operator's compartment and a one-time audible alarm outside the operator's compartment when the equipment is put in reverse?

        Can the horn and backup alarm be heard over the surrounding noise?

        Was the self-propelled mobile equipment operated at night?

»      If yes, does the equipment have a functional reverse-activated strobe light in lieu of an audible backup alarm of the type described above?

 

 

Other issues covered by related standards:

        Were personnel in the area warned prior to moving self-propelled mobile equipment or starting crushers?

(56.14200 or 57.14200 - warnings prior to starting or moving equipment or crushers)

(77.1607(bb) - audible or visible warning system for conveyors not visible from the starting switch)