§ 1928.51 Roll-over protective structures (ROPS) for tractors used in agricultural operations.
(a) Definitions. As used in this subpart—
Agricultural tractor means a two-or four-wheel drive type vehicle, or track vehicle, of more than 20 engine horsepower, designed to furnish the power to pull, carry, propel, or drive implements that are designed for agriculture. All self-propelled implements are excluded.
Low profile tractor means a wheeled tractor possessing the following characteristics:
(1) The front wheel spacing is equal to the rear wheel spacing, as measured from the centerline of each right wheel to the centerline of the corresponding left wheel.
(2) The clearance from the bottom of the tractor chassis to the ground does not exceed 18 inches.
(3) The highest point of the hood does not exceed 60 inches, and
(4) The tractor is designed so that the operator straddles the transmission when seated.
Tractor weight includes the protective frame or enclosure, all fuels, and other components required for normal use of the tractor. Ballast shall be added as necessary to achieve a minimum total weight of 110 lb. (50.0 kg.) per maximum power take-off horsepower at the rated engine speed or the maximum gross vehicle weight specified by the manufacturer, whichever is the greatest. Front end weight shall be at least 25 percent of the tractor test weight. In case power take-off horsepower is not available, 95 percent of net engine flywheel horsepower shall be used.