CFR > Title 30 - Mineral Resources > CHAPTER I—MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR > SUBCHAPTER K—METAL AND NONMETAL MINE SAFETY AND HEALTH (parts 56 to 58) > PART 56—SAFETY AND HEALTH STANDARDS—SURFACE METAL AND NONMETAL MINES > SUBPART M—Machinery and Equipment (§56.14000 to §56.14219) > 56.14132—Horns and backup alarms.

56.14132—Horns and backup alarms.

(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—
(i) An automatic reverse-activated signal alarm;
(ii) A wheel-mounted bell alarm which sounds at least once for each three feet of reverse movement;
(iii) A discriminating backup alarm that covers the area of obstructed view; or
(iv) An observer to signal when it is safe to back up.
(2) Alarms shall be audible above the surrounding noise level.
(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.