prevent accidental contact of a person with live parts.

(s) Equipment. This is a general term which includes fittings, devices, appliances, fixtures, apparatus, and the like, used as part of, or in connection with, an electrical power transmission and distribution system, or communication systems.

(t) Exposed. The term means not isolated or guarded.

(u) Electric supply lines. The term means those conductors used to transmit electric energy and their necessary supporting or containing structures. Signal lines of more than 400 volts to ground are always supply lines within the meaning of the rules, and those of less than 400 volts to ground may be considered as supply lines, if so run and operated throughout.

(v) Guarded. The term means protected by personnel, covered, fenced, or enclosed by means of suitable casings, barrier rails, screens mats, platforms, or other suitable devices in accordance with standard barricading techniques designed to prevent dangerous approach or contact by persons or objects.

NOTE: Wires, which are insulated but not otherwise protected, are not considered as guarded.

(w) Ground. (Reference). The term means that conductive body, usually earth, to which an electric potential is referenced.

(x) Ground (as a noun). The term means a conductive connection whether intentional or accidental, by which an electric circuit or equipment is connected to reference ground.

(y) Ground (as a verb). The term means the connecting or establishment of a connection, whether by intention or accident of an electric circuit or equipment to reference ground.

(z) Grounding electrode (ground electrode). The term grounding electrode means a conductor embedded in the earth, used for maintaining ground potential on conductors connected to it, and for dissipating into the earth current conducted to it.

(aa) Grounding electrode resistance. The term means the resistance of the grounding electrode to earth.

(bb) Grounding electrode conductor (grounding conductor). The term means a conductor used to connect equipment or the grounded circuit of a wiring system to a grounding electrode.

(cc) Grounded conductor. The term means a system or circuit conductor which is intentionally grounded.

(dd) Grounded system. The term means a system of conductors in which at least one conductor or point (usually the middle wire, or neutral point of transformer or generator windings) is intentionally grounded, either solidly or through a current-limiting device (not a current-interrupting device).

(ee) Hotline tools and ropes. The term means those tools and ropes which are especially designed for work on energized high voltage lines and equipment. Insulated aerial equipment especially designed for work on energized high voltage lines and equipment shall be considered hot line.

(ff) Insulated. The term means separated from other conducting surfaces by a dielectric substance (including air space) offering a high resistance to the passage of current.

NOTE: When any object is said to be insulated, it is understood to be insulated in suitable manner for the conditions to which it is subjected. Otherwise, it is within the purpose of this subpart, uninsulated. Insulating covering of conductors is one means of making the conductor insulated.

(gg) Insulation (as applied to cable). The term means that which is relied upon to insulate the conductor from other conductors or conducting parts or from ground.

(hh) Insulation shielding. The term means an envelope which encloses the insulation of a cable and provides an equipotential surface in contact with cable insulation.

(ii) Isolated. The term means an object that is not readily accessible to persons unless special means of access are used.

(jj) Manhole. The term means a subsurface enclosure which personnel may enter and which is used for the purpose of installing, operating, and maintaining equipment and/or cable.

(kk) Pulling tension. The term means the longitudinal force exerted on a cable during installation.

(11) Qualified person. The term means a person who by reason of experience or training is familiar with the operation to be performed and the hazards involved.

(mm) Switch. The term means a device for opening and closing or changing the connection of a circuit. In these

rules, a switch is understood to be manually operable, unless otherwise stated.

(nn) Tag. The term means a system or method of identifying circuits, systems or equipment for the purpose of alerting persons that the circuit, system or equipment is being worked on.

(00) Unstable material. The term means earth material, other than running, that because of its nature or the influence of related conditions, cannot be depended upon to remain in place without extra support, such as would be furnished by a system of shoring.

(pp) Vault. The term means an enclosure above or below ground which personnel may enter and is used for the purpose of installing, operating, and/or maintaining equipment and/or cable.

(qq) Voltage. The term means the effective (rms) potential difference between any two conductors or between a conductor and ground. Voltages are expressed in nominal values. The nominal voltage of a system or circuit is the value assigned to a system or circuit of a given voltage class for the purpose of convenient designation. The operating voltage of the system may vary above or below this value.

effectively

(rr) Voltage of an grounded circuit. The term means the voltage between any conductor and ground unless otherwise indicated.

(ss) Voltage of a circuit not effectively grounded. The term means the voltage between any two conductors. If one circuit is directly connected to and supplied from another circuit of higher voltage (as in the case of an autotransformer), both are considered as of the higher voltage, unless the circuit of lower voltage is effectively grounded, in which case its voltage is not determined by the circuit of higher voltage. Direct connection implies electric connection as distinguished from connection merely through electromagnetic or electrostatic induc

tion.

Subpart W-Rollover Protective
Structures; Overhead Protection

§ 1926.1000 Rollover protective structures (ROPS) for material handling equipment.

(a) Coverage. (1) This section applies to the following types of material han

dling 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 trac tors.

(2) The promulgation of specific standards for rollover protective structures for compactors and rubber-tired skid-steer equipment is reserved pending consideration of standards currently being developed.

(b) Equipment manufactured on or after September 1, 1972. Material handling machinery described in paragraph (a) of this section and manufactured an or after September 1, 1972, shall be equipped with rollover protective structures which meet the minimum performance standards prescribed in §§ 1926.1001 and 1926.1002, as applicable.

(c) Equipment manufactured before September 1, 1972. (1) All material handling equipment described in paragraph (a) 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 no later than the dates listed below:

(i) Machines manufactured on or af ter January 1, 1972, shall be fitted no later than April 1, 1973.

(ii) Machines manufactured between July 1, 1971, and December 31, 1971, sha be fitted no later than July 1, 1973.

(iii) Machines manufactured betweez July 1, 1970, and June 30, 1971, shall be fitted no later than January 1, 1974.

(iv) Machines manufactured between July 1, 1969, and June 30, 1970, shall be fitted no later than July 1, 1974.

(v) Machines manufactured before July 1, 1969: Reserved pending furthe study, development, and review.

(2) Rollover protective structures and supporting attachment shall meet the minimum performance criteria detaled in §§ 1926.1001 and 1926.1002, as appl cable or shall be designed, fabricated and installed in a manner which support, based on the ultimate strengt of the metal, at least two times the weight of the prime mover applied at the point of impact.

(1) 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.

(d) Remounting. ROPS removed for any reason, shall be remounted with equal quality, or better, bolts or welding as required for the original mounting.

(e) Labeling. Each ROPS shall have the following information permanently affixed to the structure:

(2) ROPS model number, if any; (3) Machine make, model, or series number that the structure is designed to fit.

(f) 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 structure requirements of the State of California, 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:

(1) State of California: Construction Safety Orders, issued by the Department of Industrial Relations pursuant to Division 5, Labor Code, § 6312, State of Callfornia.

(2) U.S. Army Corps of Engineers: General Safety Requirements, EM-3851-1 (March 1967).

(3) Bureau of Reclamation, U.S. Department of the Interior: Safety and Health Regulations for Construction. Part II (September 1971).

§ 1926.1001 Minimum performance criteria for rollover protective structures for designated scrapers, loaders, dozers, graders, and crawler tractors.

(a) General. 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 pre

scribed in paragraph (f) of this section for each type of machine described in this paragraph.

(b) The static laboratory test prescribed herein will determine the adequacy of the structures used to protect the operator under the following conditions:

(1) 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.

(2) 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.

(3) For crawler tractors and crawlertype 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°. (c) Facilities and apparatus. (1) The following material is necessary:

(1) Material, equipment, and tiedown means adequate to insure 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 deflections and lengths should also be provided.

(iii) Recommended, but not mandatory, types of test setups are illustrated in Figure W-1 for all types of equipment to which this section applies; and in Figure W-2 for rubber-tired self-propelled scrapers; Figure W-3 for rubbertired front-end loaders, rubber-tired dozers, and motor graders; and Figure W-4 for crawler tractors and crawlertype loaders.

(2) Table W-1 contains a listing of the required apparatus for all types of equipment described in paragraph (a) of this section.

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.

(e) Test procedure. The test procedure shall include the following, in the sequence indicated:

(1) 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 W-1, W-2, or W-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 offcenter, the load shall be applied on the offcenter side. For each applied load increment, the total load (lb.) versus corresponding deflection (in.) shall be plotted, and the area under the loaddeflection curve shall be calculated. This area is equal to the energy (in.-lb.) ab

DOUBLE-ACTING CYLINDER

LOAD LINK

FLOOR

ANCHOR

APPLIED FORCE

FIGURE W-4-Side-loading setup for crawler tractors and crawler loaders.

Incremental loading shall be continued until the ROPS has absorbed the amount of energy and the minimum applied load specified under paragraph (f) of this section has been reached or surpassed.

(2) 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 W-1). The load magnitude is specified in paragraph (f) (2) (iii) of this section.

(3) The low temperature impact strength of the material used in the ROPS shall be verified by suitable material tests or material certification (see paragraph (f) (2) (iv) of this section).

(f) Performance requirements-(1) General performance requirements. (1)