Guarding agricultural equipment

The purpose of 1928.57(a)(1) is to protect employees from hazards created by moving machinery parts on farm field equipment, farmstead equipment, and cotton gins.

• This means employers must control employee exposure to rotating, pinching, cutting, or other moving parts on covered agricultural equipment.
• See the overall standard at 1928.57 for how the purpose ties into specific guarding rules.

The standard 1928.57(a)(2) applies to farm field equipment, farmstead equipment, and cotton gins; however, certain detailed paragraphs do not apply to equipment manufactured before October 25, 1976, as stated in 1928.57(a)(3).

• Paragraphs that do not apply to equipment made before that date include parts of 1928.57(b)(2), 1928.57(b)(3), 1928.57(b)(4)(ii)(A), 1928.57(c)(2), 1928.57(c)(3), and 1928.57(c)(4)(ii)(A).
• For full scope and application, review 1928.57.

Employers must instruct each employee at initial assignment and at least annually in the safe operation and servicing of all covered equipment as required by 1928.57(a)(6).

• Training must cover specific safe operating practices including: keeping guards in place (1928.57(a)(6)(i)); permitting no riders except for instruction or assistance (1928.57(a)(6)(ii)); stopping the engine and disconnecting power before servicing unless it must run to be serviced (1928.57(a)(6)(iii)); making sure everyone is clear before starting (1928.57(a)(6)(iv)); and locking out electrical power for farmstead equipment maintenance (1928.57(a)(6)(v)).

Guards may protect by installation of a guard or shield, guarding by location, or when infeasible, by guardrails or fences as stated in 1928.57(a)(7). Guards and supports must be able to withstand the force of a 250-pound person leaning or falling on them unless otherwise specified, and must prevent inadvertent contact and be free of sharp edges per 1928.57(a)(8).

• Use guarding by location when no employee can inadvertently contact the hazard during operation, maintenance, or servicing (1928.57(a)(9)).
• Railings or fences are acceptable when guard/shield or guarding by location is infeasible (1928.57(a)(7)(ii)).

Guarding by location means a component is situated so that no employee can inadvertently contact the moving part during operation, maintenance, or servicing, as defined in 1928.57(a)(9).

• Practically, this can be accomplished by placing a rotating shaft or gear inside a well, behind permanent structural barriers, or where the geometry of the machine prevents access.
• The employer may also show that an exposure results only from an isolated and unforeseeable employee action to treat a component as guarded by location (1928.57(a)).

Servicing or maintenance may be performed while equipment is running only if the employer shows the equipment must be running to be properly serviced, the required guards cannot be in place during the service, and the servicing can be done safely, per 1928.57(a)(11).

• The employer must meet all three conditions in 1928.57(a)(11)(i)–(iii).
• If the machine must run, employers should provide detailed procedures and training showing how servicing will be done safely (1928.57(a)(6)(iii)).

All PTO shafts must be guarded; tractors must have an agricultural tractor master shield on the rear PTO unless removal is permitted by 1928.57(b)(1)(iii), as required by 1928.57(b)(1).

• The master shield must be strong enough to avoid permanent deformation if a 250-pound operator uses it as a step per 1928.57(b)(1)(ii).
• Prominent signs must be placed on tractors and PTO-driven equipment telling operators to keep PTO safety shields in place (1928.57(b)(1)(iv)).

If the tractor master shield must be removed for the implement to operate, the implement must include protection for the portion of the tractor PTO shaft that protrudes from the tractor, as stated in 1928.57(b)(1)(iii).

• That protection could be a fixed guard on the implement or other protective guarding so employees cannot contact the protruding rotating shaft (1928.57(b)(1)).

All mesh or nip-points of power-driven gears, belts, chains, sheaves, pulleys, sprockets, and idlers must be guarded, and all revolving shafts must be guarded except for smooth shaft ends protruding less than one-half the shaft diameter, per 1928.57(b)(2).

• See 1928.57(b)(2)(i) for nip-point guarding and 1928.57(b)(2)(ii) for the revolving-shaft exception.

Ground-driven components must be guarded according to 1928.57(b)(2)(i)–(ii) if any employee may be exposed to them while the drives are in motion, per 1928.57(b)(2)(iii).

• If the component is ground-driven but never accessible while moving, guarding by location may suffice; otherwise install guards or shields to prevent contact (1928.57(a)(7)).

Functional components that must be exposed for proper function must be guarded to the fullest extent that does not substantially interfere with normal functioning, as required by 1928.57(b)(3).

• Examples include cutterbars, flail rotors, mixing augers, and feed rolls.
• Where full enclosure would stop the machine working, provide the maximum practical guarding (guards, baffles, or fixed barriers) while still allowing the unit to perform its function (1928.57(b)(3)).

Guards, shields, and access doors must be in place during operation, and if removing a guard will expose components that continue to rotate after power is off, the employer must provide a visible or audible warning and post a safety sign telling employees to look and listen for rotation and not to remove the guard until parts stop, per 1928.57(b)(4)(i)–(ii).

• The warning requirement is in 1928.57(b)(4)(ii)(A) and the sign content in 1928.57(b)(4)(ii)(B).
• These measures help prevent injury from coast-down or inertia-driven rotation after shutdown.

Farmstead equipment must have all PTO shafts guarded either by a master shield like tractors or by other protective guarding, and signs must be posted to keep safety shields in place, as required in 1928.57(c)(1)(i)–(iii).

• The requirements mirror field equipment PTO rules in 1928.57(b)(1).
• If the tractor master shield is removed for design reasons, the equipment must still protect the protruding shaft (1928.57(c)(1)(ii)).

Yes. 1928.57(c)(2)(ii)(A) allows smooth shafts and shaft ends without projections that revolve at less than 10 rpm on feed handling equipment used on top surfaces in bulk storage facilities to be unguarded.

• This is a narrow exception and applies only where the shaft is smooth, under 10 rpm, and used on the top surface of materials in bulk storage (1928.57(c)(2)(ii)(A)).

Exposed auger flighting on portable grain augers must be guarded with either grating-type guards or solid baffle style covers meeting the size and spacing limits in 1928.57(c)(3)(iii)(A)–(B).

• Grating openings for material flow may be no larger than 4¾ inches with each opening no larger than 10 square inches (1928.57(c)(3)(iii)(A)).
• For solid baffles, slotted openings shall be no wider than 1½ inches and not closer than 3½ inches to the exposed flighting; other placement rules include the opening located at least 2½ inches from flighting (1928.57(c)(3)(iii)(B)).

If removing an access door exposes components that continue to rotate after power is disengaged, the employer must provide a readily visible or audible warning of rotation and a safety sign instructing employees to look and listen for rotation and not remove the door until parts stop, per 1928.57(c)(4)(ii).

• This mirrors the field equipment rule at 1928.57(b)(4)(ii) and is intended to prevent injuries from coasting parts.

Employers must prevent application of electrical power from outside the immediate and exclusive control of maintenance workers by providing either a positive locking means on the main switch operable only by maintenance employees or by physically locating a disconnect on the equipment for bulk storage material handling, per 1928.57(c)(5)(i)(A)–(B).

• The locking means ensures only the person performing maintenance can re-energize the equipment (1928.57(c)(5)(i)(A)).

Circuit protection devices must be manual-reset except where the employer shows manual reset is infeasible due to the operation, distances, and time employees spend in the area, and where an electrical disconnect is within 15 feet or a sign warns the employee that the motor could automatically reset, as allowed in 1928.57(c)(5)(ii)(A)–(C).

• If the employer relies on the exception, there must be an accessible disconnect within 15 feet (1928.57(c)(5)(ii)(B)) and a prominent sign warning about automatic reset (1928.57(c)(5)(ii)(C)).

Gin stand main and miscellaneous drives must be completely enclosed, guarded by location, or guarded by railings consistent with 1928.57(a)(7), and any hazardous component within 15 horizontal inches of a railing must be completely enclosed, per 1928.57(d)(1)(i)–(ii).

• Railings should be about 42 inches high with a midrail and be strong enough to withstand 200 pounds on the toprail (1928.57(d)(1)(iii)).
• Table D-1 in 1928.57(d)(1)(iii) provides minimum guard panel material and opening size examples.

Chains and sprockets must be completely enclosed unless guarded by location due to packed bearings or extension lubrication fittings; pulley guards may be limited to face sections where full enclosure would cause lint fire hazards; projecting shaft ends not guarded by location must be smooth, capped or sleeved, and not protrude more than one-half the shaft diameter, per 1928.57(d)(1)(v)–(vii).

• For pulleys where only the face is guarded because of lint buildup, the guard must extend at least 6 inches beyond the pulley rim on in-running and off-running sides and at least 2 inches from the rim/face elsewhere (1928.57(d)(1)(vi)).

Gin stands must have permanently installed guards to prevent contact with gin saws in motion; moving saws on lint cleaners with access doors must have fixed barrier guards preventing finger/hand contact; balers must have an interlock preventing upper gates from opening while the tramper operates, per 1928.57(d)(2)(i)–(iii).

• These are specific functional-component and access-control measures tailored to ginning hazards (1928.57(d)(2)).

Yes. A warning device that provides an audible signal must be installed in all cotton gins to indicate when any or all machines comprising the gin are about to be started, as required by 1928.57(d)(3).

• The audible signal helps ensure employees are clear of moving parts before startup and is part of the gin-specific guarding requirements (1928.57(d)).

Cotton gins are regulated as agricultural operations under Part 1928, and their guarding is specifically covered by 1928.57, as clarified in OSHA's Cotton Gins memorandum at https://www.osha.gov/laws-regs/standardinterpretations/2002-08-06.

• The 2002 memorandum explains that cotton ginning falls within OSHA's agricultural standards and that Part 1928 specifically covers cotton gins.
• If hazards at gins are not covered by Part 1928, they may be addressed under the general duty clause, but the primary standard for gin guarding is 1928.57 (see https://www.osha.gov/laws-regs/standardinterpretations/2002-08-06).