turnover, overturn or roll-over is the major cause
of tractor-related deaths.
overturn deaths are prevented with seat belts and
roll-over protective structures (ROPS).
Occupational Safety and Health Administration (OSHA)
has issued regulations for ROPS utilization.
older tractors are not ROPS equipped, but ROPS can
be purchased from the dealer.
turnover is by far the major cause of tractor-related deaths.
In a Johns Hopkins University study of tractor-related deaths
between 1975 and 1981, 45 percent or 1,163 of the 2,566 total
deaths were caused by roll-over accidents. Similarly, a 12-year
study of Colorado agriculture-related deaths (1978-1990) revealed
50 percent of the tractor-related deaths were due to roll-over.
of these deaths could have been prevented if the tractor had
been equipped with a roll-over protective structure (ROPS)
at a cost of $400 to $600. A ROPS is a cab or frame that protects
operators and minimizes the possibility of serious injury
in an accidental upset.
175 tractor turnover accidents reported in Nebraska from January
1966 to January 1972, 78 were fatalities, 93 were injuries
and four were noninjuries. Eight of the 175 tractors were
equipped with ROPS and resulted in four non-injury and four
Service in Action 5.016, General tractor safety, for additional
information on safe operation.
Occupational Safety and Health Administration (OSHA) has issued
regulations for ROPS utilization.
tractors manufactured after October 25, 1976, shall meet the
roll-over protective structure (ROPS) shall be provided
by the employer for each tractor operated by an employee.
ROPS are required by this section, the employers shall:
each tractor with a seat belt that meets the requirements
of SAE standard J4C;
that each employee uses the seat belt and tightens the
belt sufficiently to confine the employee."
profile' tractors used in orchards, vineyards or hop yards
where the vertical clearance requirements substantially
interfere with normal operations and their use is incidental
to the work performed.
profile' tractors used inside a farm building or greenhouse
in which the vertical clearance is sufficient to allow a
ROPS equipped tractor to operate, and their use is incidental
to the work performed.
used with mounted equipment that is incompatible with ROPS
(e.g., cornpickers, cotton strippers, vegetable pickers
and fruit harvesters).
means a two- or four-wheel drive 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
profile tractor means a wheeled tractor possessing 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;
clearance from the bottom of the tractor chassis to the
ground does not exceed 18 inches;
highest point of the hood does not exceed 60 inches; and
tractor is designed so that the operator straddles the transmission
ROPS are removed for any reason, remount them to meet the performance
requirements specified in the standard.
ROPS should have a label, permanently affixed to the structure,
stating: manufacturer's or fabricator's name and address; ROPS
model number (if any); tractor makes, models or series numbers
that the structure is designed to fit; and whether or not the
ROPS model was tested in accordance with the requirements of
June 1, 1975, every employee who operates an agricultural tractor
should be informed of the operating practices contained below
and any other practices dictated by the work environment. Such
information must be provided at the time of initial assignment
and at least annually thereafter.
fasten seat belt if the tractor has a ROPS.
possible, avoid operating the tractor near ditches, embankments
speed when turning, crossing slopes and on rough, slick
or muddy surfaces.
off slopes too steep for safe operation.
where you are going, especially at row ends, on roads and
not permit others to ride.
only to the drawbar and hitch points recommended by tractor
the tractor smoothly--no jerky turns, starts or stops.
tractor is stopped, set brakes securely and use park lock
the 1984 Session, the National Institute for Farm Safety (NIFS)
and the Agricultural Division of the National Safety Council
(NSC) transmitted resolutions to the American Society of Agricultural
Engineers (ASAE) requesting ROPS be standard equipment on agricultural
tractors. ROPS were designed in the early 1960's with the intended
most upsets to 90 degrees; and
the operator in upsets beyond 90 degrees.
ROPS became available on John Deere farm tractors. The ASAE
published their first standards for ROPS design and utilization
in 1967. The 1984 ASAE Standard: ASAE 5383.1 "RollOver Protective
Structures (ROPS) for Wheeled Agricultural Tractors" establishes
test and performance requirements for ROPS.
the frame or enclosure meets these standards to provide roll-over
protection. Some structures are designed only for weather
protection. In 1985, some tractor manufacturers are making
ROPS standard on all new tractors. Many dealers can install
a ROPS on older model tractors. Numerous roll-over injuries
are reported with the use of small garden tractors without
ROPS. OSHA does not require the use of ROPS with these small
tractors, but installation is beneficial to the operator.
overturns can be prevented. Tractor operation determines overturns.
Stresses caused by vibration, noise, fumes and overwork increase
the chances for overturn accidents. Operator enclosures can
reduce stresses by filtering air and reducing noise and vibration.
slope, tractor speed, turning radius, rear axle torque and
center of gravity are interrelated factors that determine
tractor turnover potential. Mathematical computer models,
designed to simulate tractor turnovers and verified by full-scale
tests, have been useful for designing more stable tractors
(Denny, 1974). A system to determine tractor turnover potential
utilizing the simulation model and sensor field and tractor
operating conditions is being developed (Murphy, 1982). The
ultimate goal is an audible warning system that informs the
operator of high turnover potential.
Publication #: 5.018
Cooperative Extension, Colorado State University. Published
July 1985. Revised October 1992. Copyright 1992. For more
information, contact your county Cooperative Extension office.
Colorado State University Cooperative Extension agricultural
engineer and associate professor, agricultural and chemical
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