296-155-950 Rollover protective
structures (ROPS) for material handling equipment. 296-155-955 Minimum performance
criteria for rollover protective structures for designated scrapers,
loaders, dozers,
graders, and crawler tractors. 296-155-960 Protective
frame (ROPS) test procedures and performance requirements for wheel-type
agricultural and industrial tractors used in construction. 296-155-965 Overhead
protection for operators of agricultural and industrial tractors.
WAC 296-155-950 Rollover
protective structures (ROPS) for material handling equipment.
(1) Coverage.
(a) This section applies to the following types of material handling
equipment: To all rubber-tired, self-propelled scrapers, rubber-tired
front-end loaders, rubber-tired dozers, wheel-type agricultural and
industrial tractors, crawler tractors, crawler-type loaders, and motor
graders, with or without attachments, that are used in construction
work. This requirement does not apply to sideboom pipelaying tractors.
(b) The promulgation of specific standards for rollover protective
structures for compactors and rubber-tired skidsteer equipment is reserved
pending consideration of standards currently being developed.
(2) Equipment manufactured on or after September 1, 1972, Material
handling machinery described in subsection (1) of this section
and manufactured on or after September 1, 1972, shall be equipped
with rollover protective structures which meet the minimum performance
standards prescribed in WAC
296-155-955 and 296-155-960,
as applicable.
(3) Equipment manufactured before September 1, 1972.
(a) All material handling equipment described in subsection (1) of
this section and manufactured or placed in service (owned or operated
by the employer) prior to September 1, 1972, shall be fitted with rollover
protective structures.
Machines manufactured before July 1, 1969; Reserved pending further
study, development, and review.
(b) Rollover protective structures and supporting attachment
shall meet the minimum performance criteria detailed in WAC
296-155-955 and 296-155-960,
as applicable or shall be designed, fabricated, and installed
in a manner which will support, based on the ultimate strength
of the metal, at least two times the weight of the prime mover
applied at the point of impact.
(i) The design objective shall be to minimize the likelihood of a
complete overturn and thereby minimize the possibility of the operator
being crushed as a result of a rollover or upset.
(ii) The design shall provide a vertical clearance of at least 52
inches from the work deck to the ROPS at the point of ingress or egress.
(4) Remounting. ROPS removed for any reason, shall be remounted with
equal quality, or better, bolts or welding as required for the original
mounting.
(5) Labeling. Each ROPS shall have the following information permanently
affixed to the structure:
(a) Manufacturer or fabricator's name and address;
(b) ROPS model number, if any;
(c) Machine make, model, or series number that the structure is designed
to fit.
(6) Machines meeting certain existing governmental requirements. Any
machine in use, equipped with rollover protective structures, shall be
deemed in compliance with this section if it meets the rollover protective
structures requirements of the U.S. Army Corps of Engineers, or the Bureau
of Reclamation of the U.S. Department of the Interior in effect on April
5, 1972. The requirements in effect are:
(a) U.S. Army Corps of Engineers: General Safety Requirements, EM-385-1-1
(March 67).
(b) Bureau of Reclamation, U.S. Department of the Interior: Safety
and Health Regulations for Construction, Part II (September 1971).
(7) ROPS meeting the criteria set forth in SAE J1040 a and SAE J1040
b shall be regarded as substantially meeting the requirements of this
section, even if they do not meet all the criteria set forth in earlier
criteria documents on which the present standard is based.
WAC 296-155-955 Minimum
performance criteria for rollover protective structures for designated
scrapers, loaders, dozers, graders, and crawler tractors.
(1) Definitions. For purposes of this section, “vehicle weight”
means the manufacturer's maximum weight of the prime mover for rubber-tired
self-propelled scrapers. For other types of equipment to which this section
applies, “vehicle weight” means the manufacturer's maximum recommended
weight of the vehicle plus the heaviest attachment.
(2) General.
(a) This section prescribes minimum performance criteria for rollover
protective structures (ROPS) for rubber-tired self-propelled scrapers;
rubber-tired front-end loaders and rubber-tired dozers; crawler tractors,
and crawler-type loaders, and motor graders. The vehicle and ROPS as
a system shall have the structural characteristics prescribed in subsection
(7) of this section for each type of machine described in this subsection.
(b) Equipment listed in subsection (2)(a) of this section may be exempted
from the requirements for fitment of ROPS where it can be shown, to
the satisfaction of the department, that the equipment will only be
used where no rollover hazard will exist.
(3) The static laboratory test prescribed herein will determine the adequacy
of the structures used to protect the operator under the following conditions:
(a) For rubber-tired self-propelled scrapers, rubber-tired front-end
loaders, and rubber-tired dozers: Operating between 0 and 10 miles per
hour over hard clay where rollover would be limited to a maximum roll
angle of 360° down a slope of 30° maximum.
(b) For motor graders: Operating between 0 and 10 miles per hour over
hard clay where rollover would be limited to 360° down a slope of 30°
maximum.
(c) For crawler tractors and crawler-type loaders: Operating between
0 and 10 miles per hour over hard clay where rollover would be limited
to a maximum roll angle of 360° down a slope of 45°.
(4) Facilities and apparatus.
(a) The following material is necessary:
(i) Material, equipment, and tiedown means adequate to ensure that
the ROPS and its vehicle frame absorb the applied energy.
(ii) Equipment necessary to measure and apply loads to the ROPS.
Adequate means to measure deflection and lengths should also be provided.
(iii) Recommended, but not mandatory, types of test setups are illustrated
in Figure V-1 for all types of equipment to which this section applies;
and in Figure V-2 for rubber-tired self-propelled scrapers; Figure
V-3 for rubber-tired front-end loaders, rubber-tired dozers, and motor
graders; and Figure V-4 for crawler tractors and crawler-type loaders.
(b) Table V-1 contains a listing of the required apparatus for all
types of equipment described in subsection (2)(a) of this section.
TABLE V-1
Means
to measure
Accuracy
Deflection of ROPS,
inches
± 5% of deflection
measured.
Vehicle weight, pounds
± 5% of the weight
measured.
Force applied to
frame, pounds
± 5% of force measured.
Dimensions of critical
zone, inches.
± 0.5 in.
(5) Vehicle condition. The ROPS to be tested must be attached to the
vehicle structure in the same manner as it will be attached during vehicle
use. A totally assembled vehicle is not required. However, the vehicle
structure and frame which support the ROPS must represent the actual vehicle
installation. All normally detachable windows, panels, or nonstructural
fittings shall be removed so that they do not contribute to the strength
of the ROPS.
(6) Test procedure. The test procedure shall include the following, in
the sequence indicated:
(a) Energy absorbing capabilities of ROPS shall be verified when loaded
laterally by incrementally applying a distributed load to the longitudinal
outside top member of the ROPS, as shown in Figure V-1, V-2 or V-3 as
applicable. The distributed load must be applied so as to result in
approximately uniform deflection of the ROPS. The load increments should
correspond with approximately 0.5 in. ROPS deflection increment in the
direction of the load application, measured at the ROPS top edge. Should
the operator's seat be off center, the load shall be applied on the
off center side. For each applied load increment, the total load (lb.)
versus corresponding deflection (in.) shall be plotted, and the area
under the load-deflection curve shall be calculated. This area is equal
to the energy (in.-lb.) absorbed by the ROPS. For a typical load-deflection
curve and calculation method, see Figure V-5.
Incremental loading shall be continued until the ROPS has absorbed
the amount of energy and the minimum applied load specified under subsection
(7) of this section has been reached or surpassed.
(b) To cover the possibility of the vehicle coming to rest on its top,
the support capability shall be verified by applying a distributed vertical
load to the top of the ROPS so as to result in approximately uniform
deflection (see Figure V-1).The load magnitude is specified in subsection
(7)(b)(iii) of this section.
(c) The low temperature impact strength of the material used in the
ROPS shall be verified by suitable material tests or material certification
(see subsection (7)(b)(iv) of this section).
FIGURE V-1
Vertical loading setup for all types of equipment described in
WAC 296-155-955(1).
FIGURE V-2
Test setup for rubber-tired self-propelled scrapers.
FIGURE V-3
Test setup for rubber-tired front-end loaders, rubber-tired dozers,
and motor graders.
FIGURE V-4
Side-loading setup for crawler tractors and crawler
loaders.
FIGURE V-5
Determination of energy area under force deflection curve for all
types of ROPS equipment defined in WAC 296-155-955.
(7) Performance requirements.
(a) General performance requirements.
(i) No repairs or straightening of any member shall be carried out
between each prescribed test.
(ii) During each test, no part of the ROPS shall enter the critical
zone as detailed in SAE J397 (1969). Deformation of the ROPS shall
not allow the plane of the ground to enter this zone.
(b) Specific performance requirements.
(i) The energy requirement for purposes of meeting the requirements
of subsection (6)(a) of this section is to be determined by referring
to the plot of the energy versus weight of vehicle (see Figure V-6
for rubber-tired self-propelled scrapers; Figure V-7 for rubber-tired
front-end loaders and rubber-tired dozers; Figure V-8 for crawler
tractors and crawler-type loaders; and Figure V-9 for motor graders.
For purposes of this section, force and weight are measured as pounds;
energy (U) is measured as inch-pounds).
FIGURE V-6
Energy absorbed versus vehicle weight.
FIGURE V-7
Energy absorbed versus vehicle weight.
FIGURE V-8
Energy absorbed versus vehicle weight.
FIGURE V-9
Energy absorbed versus vehicle weight.
FIGURE V-10
Minimum horizontal load factor for self-propelled scrapers.
(ii) The applied load must attain at least a value which is determined
by multiplying the vehicle weight by the corresponding factor shown
in Figure V-10 for rubber-tired self-propelled scrapers; in Figure
V-11 for rubber-tired front-end loaders and rubber-tired dozers; in
Figure V-12 for crawler tractors and crawler-type loaders; and in
Figure V-13 for motor graders.
FIGURE V-11
Minimum horizontal load factor for rubber-tired loaders
and dozers.
FIGURE V-12
Minimum horizontal load factor for crawler tractors and
crawler-type loaders.
FIGURE V-13
Minimum horizontal load factor for motor graders.
(iii) The load magnitude for purposes of compliance with subsection
(6)(b) of this section is equal to the vehicle weight. The test of
load magnitude shall only be made after the requirements of subdivision
(b)(i) of this subsection are met.
(iv) Material used in the ROPS must have the capability of performing
at zero degrees Fahrenheit, or exhibit Charpy V notch impact strength
of 8 foot-pounds at minus 20° Fahrenheit. This is a standard Charpy
specimen as described in American Society of Testing and Materials
A 370, Methods and Definitions for Mechanical Testing of Steel Products.
The purpose of this requirement is to reduce the tendency of brittle
fracture associated with dynamic loading, low temperature operation,
and stress raisers which cannot be entirely avoided on welded structures.
(8) Source of standard. This standard is derived from, and restates,
the following Society of Automotive Engineers Recommended Practices: SAE
J320a, Minimum Performance Criteria for Roll-Over Protective Structure
for Rubber-Tired, Self-Propelled Scrapers; SAE J394, Minimum Performance
Criteria for Roll-Over Protective Structure for Rubber-Tired Front- End
Loaders and Rubber-Tired Dozers; SAE J395, Minimum Performance Criteria
for Roll-Over Protective Structure for Crawler Tractors and Crawler-Type
Loaders; and SAE J396, Minimum Performance Criteria for Roll-Over Protective
Structure for Motor Graders. These recommended practices shall be resorted
to in the event that questions of interpretation arise. The recommended
practices appear in the 1971 SAE Handbook, which may be examined in each
of the district offices of the department of labor and industries.
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