OSHA general industry machine guarding study guide
Subpart O of OSHA's general industry rules (29 CFR 1910.211 to 1910.219) covers machinery and machine guarding. This guide sets out what the rule text states in 1910.212 (general requirements for all machines), the basics of 1910.213 (woodworking machinery), 1910.215 (abrasive wheels), a few clearly stated basics of 1910.217 (mechanical power presses) and 1910.219 (mechanical power-transmission apparatus). Consensus standards the rule incorporates (such as ANSI B7.1-1970) are only named here, not summarized. Every point links to the regulation and quotes its exact words.
General machine guarding
One or more methods of machine guarding must be provided to protect the operator and other employees in the machine area from hazards such as the point of operation, ingoing nip points, rotating parts, flying chips and sparks. The rule's examples of guarding methods are barrier guards, two-hand tripping devices and electronic safety devices.
“One or more methods of machine guarding shall be provided to protect the operator and other employees in the machine area from hazards such as those created by point of operation, ingoing nip points, rotating parts, flying chips and sparks. Examples of guarding methods are-barrier guards, two-hand tripping devices, electronic safety devices, etc.”
Guards must be affixed to the machine where possible, and secured elsewhere if attachment to the machine is not possible for any reason. A guard must not be an accident hazard in itself.
“Guards shall be affixed to the machine where possible and secured elsewhere if for any reason attachment to the machine is not possible. The guard shall be such that it does not offer an accident hazard in itself.”
The point of operation is the area on a machine where work is actually performed on the material being processed.
“Point of operation is the area on a machine where work is actually performed upon the material being processed.”
The point of operation of a machine whose operation exposes an employee to injury must be guarded. The guarding device must conform to any appropriate standards for it or, where no specific standard applies, be designed and built to keep the operator from having any part of the body in the danger zone during the operating cycle.
“The point of operation of machines whose operation exposes an employee to injury, shall be guarded. The guarding device shall be in conformity with any appropriate standards therefor, or, in the absence of applicable specific standards, shall be so designed and constructed as to prevent the operator from having any part of his body in the danger zone during the operating cycle.”
Special hand tools for placing and removing material must let the operator handle material without placing a hand in the danger zone. These tools do not replace other required guarding; they can only supplement it.
“Special handtools for placing and removing material shall be such as to permit easy handling of material without the operator placing a hand in the danger zone. Such tools shall not be in lieu of other guarding required by this section, but can only be used to supplement protection provided.”
Revolving drums, barrels and containers must be guarded by an enclosure interlocked with the drive mechanism, so the barrel, drum or container cannot revolve unless the guard enclosure is in place.
“Revolving drums, barrels, and containers shall be guarded by an enclosure which is interlocked with the drive mechanism, so that the barrel, drum, or container cannot revolve unless the guard enclosure is in place.”
When the periphery of a fan's blades is less than 7 feet above the floor or working level, the blades must be guarded, and the guard may have openings no larger than 1/2 inch.
“When the periphery of the blades of a fan is less than seven (7) feet above the floor or working level, the blades shall be guarded. The guard shall have openings no larger than one-half (1⁄2) inch.”
Machines designed for a fixed location must be securely anchored to prevent walking or moving.
“Machines designed for a fixed location shall be securely anchored to prevent walking or moving.”
Woodworking machinery
An automatic cutoff saw that strokes continuously without the operator being able to control each stroke must not be used.
“Any automatic cutoff saw that strokes continuously without the operator being able to control each stroke shall not be used.”
Belts, pulleys, gears, shafts and moving parts on woodworking machines must be guarded under the specific requirements of 1910.219 (power-transmission apparatus).
“All belts, pulleys, gears, shafts, and moving parts shall be guarded in accordance with the specific requirements of § 1910.219.”
The rule recommends (it does not require) that each power-driven woodworking machine have a disconnect switch that can be locked in the off position.
“It is recommended that each power-driven woodworking machine be provided with a disconnect switch that can be locked in the off position.”
Each machine must have a mechanical or electrical power control that lets the operator cut off its power without leaving his position at the point of operation.
“A mechanical or electrical power control shall be provided on each machine to make it possible for the operator to cut off the power from each machine without leaving his position at the point of operation.”
Where injury to the operator might result if motors restarted after a power failure, provision must be made to keep machines from restarting automatically when power comes back.
“On applications where injury to the operator might result if motors were to restart after power failures, provision shall be made to prevent machines from automatically restarting upon restoration of power.”
Each circular hand-fed ripsaw must be guarded by a hood that completely encloses the part of the saw above the table and the part above the material being cut.
“Each circular hand-fed ripsaw shall be guarded by a hood which shall completely enclose that portion of the saw above the table and that portion of the saw above the material being cut.”
Each hand-fed circular ripsaw must have a spreader to keep material from squeezing the saw or being thrown back on the operator.
“Each hand-fed circular ripsaw shall be furnished with a spreader to prevent material from squeezing the saw or being thrown back on the operator.”
A spreader is not required for grooving, dadoing or rabbeting, but it must be put back immediately when that work is done.
“The provision of a spreader in connection with grooving, dadoing, or rabbeting is not required. On the completion of such operations, the spreader shall be immediately replaced.”
Each hand-fed circular ripsaw must also have nonkickback fingers or dogs placed to oppose the saw's tendency to pick up the material or throw it back toward the operator.
“Each hand-fed circular ripsaw shall be provided with nonkickback fingers or dogs so located as to oppose the thrust or tendency of the saw to pick up the material or to throw it back toward the operator.”
Not covered here
The detailed rules for each other kind of woodworking machine in 1910.213 (resaws, self-feed and swing cutoff saws, bandsaws, tenoning machines, shapers, planers, lathes, sanders and veneer cutters). We only write what an official source states, so study these parts with your certifying program's materials.
Woodworking inspection and maintenance
Dull, badly set, improperly filed or improperly tensioned saws must be removed from service immediately, before they begin to make the material stick, jam or kick back when fed at normal speed. Saws with gum on their sides must be cleaned immediately.
“Dull, badly set, improperly filed, or improperly tensioned saws shall be immediately removed from service, before they begin to cause the material to stick, jam, or kick back when it is fed to the saw at normal speed. Saws to which gum has adhered on the sides shall be immediately cleaned.”
Sharpening or tensioning of saw blades or cutters may be done only by persons of demonstrated skill in this kind of work.
“Sharpening or tensioning of saw blades or cutters shall be done only by persons of demonstrated skill in this kind of work.”
All cracked saws must be removed from service.
“All cracked saws shall be removed from service.”
Inserting wedges between the saw disk and the collar to make a "wobble saw" is not permitted.
“The practice of inserting wedges between the saw disk and the collar to form what is commonly known as a "wobble saw" shall not be permitted.”
Push sticks or push blocks, in the several sizes and types suitable for the work, must be provided at the work place.
“Push sticks or push blocks shall be provided at the work place in the several sizes and types suitable for the work to be done.”
The knife blade of a jointer must be installed and adjusted so it does not protrude more than 1/8 inch beyond the cylindrical body of the head.
“The knife blade of jointers shall be so installed and adjusted that it does not protrude more than one-eighth inch beyond the cylindrical body of the head.”
Abrasive wheels
Abrasive wheels may be used only on machines with the safety guards defined in 1910.215. The listed exceptions are wheels used for internal work while within the work being ground; mounted wheels 2 inches and smaller in diameter used in portable operations; and Types 16, 17, 18, 18R and 19 cones, plugs and threaded hole pot balls where the work offers protection.
“Abrasive wheels shall be used only on machines provided with safety guards as defined in the following paragraphs of this section, except: (i) Wheels used for internal work while within the work being ground; (ii) Mounted wheels, used in portable operations, 2 inches and smaller in diameter; and (iii) Types 16, 17, 18, 18R, and 19 cones, plugs, and threaded hole pot balls where the work offers protection.”
The safety guard must cover the spindle end, nut and flange projections, be mounted to keep proper alignment with the wheel, and have fastenings stronger than the guard, apart from the exceptions listed in 1910.215(a)(2).
“The safety guard shall cover the spindle end, nut, and flange projections. The safety guard shall be mounted so as to maintain proper alignment with the wheel, and the strength of the fastenings shall exceed the strength of the guard, except:”
On offhand grinding machines, work rests must be used to support the work. They must be kept adjusted closely to the wheel with a maximum opening of 1/8 inch, so the work cannot jam between the wheel and the rest, which may break the wheel.
“On offhand grinding machines, work rests shall be used to support the work. They shall be of rigid construction and designed to be adjustable to compensate for wheel wear. Work rests shall be kept adjusted closely to the wheel with a maximum opening of one-eighth inch to prevent the work from being jammed between the wheel and the rest, which may cause wheel breakage.”
That work rest must be securely clamped after each adjustment, and the adjustment must not be made with the wheel in motion.
“The work rest shall be securely clamped after each adjustment. The adjustment shall not be made with the wheel in motion.”
Natural sandstone wheels and metal, wooden, cloth or paper discs with a layer of abrasive on the surface are not covered by 1910.215.
“Natural sandstone wheels and metal, wooden, cloth, or paper discs, having a layer of abrasive on the surface are not covered by this section.”
For the safety guards described in 1910.215(b)(3) and (4) (the paragraphs on bench and floor stands and on cylindrical grinders), where the operator stands in front of the opening, the distance between the wheel periphery and the adjustable tongue (or the end of the peripheral member at the top) must never exceed 1/4 inch.
“Safety guards of the types described in subparagraphs (3) and (4) of this paragraph, where the operator stands in front of the opening, shall be constructed so that the peripheral protecting member can be adjusted to the constantly decreasing diameter of the wheel. The maximum angular exposure above the horizontal plane of the wheel spindle as specified in paragraphs (b) (3) and (4) of this section shall never be exceeded, and the distance between the wheel periphery and the adjustable tongue or the end of the peripheral member at the top shall never exceed one-fourth inch.”
Where the work is applied to the wheel above the horizontal centerline (top grinding), the exposure of the wheel periphery must be as small as possible and must not exceed 60 degrees.
“Where the work is applied to the wheel above the horizontal centerline, the exposure of the grinding wheel periphery shall be as small as possible and shall not exceed 60°.”
All abrasive wheels must be mounted between flanges not less than one-third the diameter of the wheel, apart from the exceptions listed in 1910.215(c)(1)(i).
“All abrasive wheels shall be mounted between flanges which shall not be less than one-third the diameter of the wheel. (i) Exceptions:”
Not covered here
The guard exposure angles for each other machine type, the guard material and thickness tables, and the guard design specifications of ANSI B7.1-1970, which 1910.215(b)(12) incorporates by reference and this guide only names. We only write what an official source states, so study these parts with your certifying program's materials.
Mounting abrasive wheels
Immediately before mounting, every wheel must be closely inspected and sounded by the user (the ring test) to make sure it was not damaged in transit, storage or otherwise.
“Immediately before mounting, all wheels shall be closely inspected and sounded by the user (ring test) to make sure they have not been damaged in transit, storage, or otherwise.”
The machine's spindle speed must be checked before the wheel is mounted, to be certain it does not exceed the maximum operating speed marked on the wheel.
“The spindle speed of the machine shall be checked before mounting of the wheel to be certain that it does not exceed the maximum operating speed marked on the wheel.”
For the ring test, the rule says wheels should be tapped gently with a light nonmetallic implement, such as a screwdriver handle for light wheels or a wooden mallet for heavier wheels. A wheel that sounds cracked (dead) must not be used.
“Wheels should be tapped gently with a light nonmetallic implement, such as the handle of a screwdriver for light wheels, or a wooden mallet for heavier wheels. If they sound cracked (dead), they shall not be used.”
Wheels must be dry and free from sawdust for the ring test, or the sound will be deadened. The rule also notes that organic bonded wheels do not give the same clear metallic ring as vitrified and silicate wheels.
“Wheels must be dry and free from sawdust when applying the ring test, otherwise the sound will be deadened. It should also be noted that organic bonded wheels do not emit the same clear metallic ring as do vitrified and silicate wheels.”
Grinding wheels must fit freely on the spindle and stay free under all grinding conditions.
“Grinding wheels shall fit freely on the spindle and remain free under all grinding conditions.”
Mechanical power presses
Press brakes, hydraulic and pneumatic power presses, bulldozers, hot bending and hot metal presses, forging presses and hammers, riveting machines and similar fastener applicators are excluded from 1910.217.
“Press brakes, hydraulic and pneumatic power presses, bulldozers, hot bending and hot metal presses, forging presses and hammers, riveting machines and similar types of fastener applicators are excluded from the requirements of this section.”
The employer must provide and ensure the use of point of operation guards, or properly applied and adjusted point of operation devices, on every operation performed on a mechanical power press.
“It shall be the responsibility of the employer to provide and insure the usage of "point of operation guards" or properly applied and adjusted point of operation devices on every operation performed on a mechanical power press.”
That point of operation requirement does not apply when the point of operation opening is 1/4 inch or less.
“The requirement of paragraph (c)(1)(i) of this section shall not apply when the point of operation opening is one-fourth inch or less.”
Hand feeding tools are for placing and removing material in and from the press. They are not a point of operation guard or protection device and must not be used instead of the required guards or devices.
“Hand feeding tools are intended for placing and removing materials in and from the press. Hand feeding tools are not a point of operation guard or protection device and shall not be used in lieu of the "guards" or devices required in this section.”
The employer must provide and enforce the use of safety blocks whenever dies are being adjusted or repaired in the press.
“The employer shall provide and enforce the use of safety blocks for use whenever dies are being adjusted or repaired in the press.”
Under the directed component of the press inspection program, the employer must inspect and test each press on a regular basis at least once a week to check the condition of the clutch/brake mechanism, antirepeat feature and single-stroke mechanism.
“Under the directed component of the inspection program, the employer shall: (A) Inspect and test each press on a regular basis at least once a week to determine the condition of the clutch/brake mechanism, antirepeat feature, and single-stroke mechanism;”
That weekly directed component (1910.217(e)(1)(ii)) does not apply to presses that comply with 1910.217(b)(13) and (14).
“Paragraph (e)(1)(ii) of this section does not apply to presses that comply with paragraphs (b)(13) and (14) of this section.”
The employer must train and instruct the operator in the safe method of work before the operator starts work on any operation covered by 1910.217, and make sure through adequate supervision that correct procedures are followed.
“The employer shall train and instruct the operator in the safe method of work before starting work on any operation covered by this section. The employer shall insure by adequate supervision that correct operating procedures are being followed.”
The employer must report all point-of-operation injuries to operators or other employees within 30 days of the occurrence, either to the Director of OSHA's Directorate of Standards and Guidance (or electronically at the web address the rule gives) or to the State agency administering an approved state plan.
“The employer shall report, within 30 days of the occurrence, all point-of-operation injuries to operators or other employees to either the Director of the Directorate of Standards and Guidance at OSHA, U.S. Department of Labor, Washington, DC 20210 or electronically at http://www.osha.gov/pls/ oshaweb/mechanical.html; or to the State Agency administering a plan approved by the Assistant Secretary of Labor for Occupational Safety and Health.”
Not covered here
Most of 1910.217: clutch and control system details, safeguarding device specifications and Table O-10 openings, die design rules, and presence sensing device initiation (PSDI) in 1910.217(h) and its appendices. We only write what an official source states, so study these parts with your certifying program's materials.
Power-transmission apparatus
1910.219 covers all power-transmission belts except these when running at 250 feet per minute or less: flat belts 1 inch or less wide, flat belts 2 inches or less wide that have no metal lacings or fasteners, round belts 1/2 inch or less in diameter, and single strand V-belts 13/32 inch wide or less.
“This section covers all types and shapes of power-transmission belts, except the following when operating at two hundred and fifty (250) feet per minute or less: (i) Flat belts one (1) inch or less in width, (ii) flat belts two (2) inches or less in width which are free from metal lacings or fasteners, (iii) round belts one-half (1⁄2) inch or less in diameter; and (iv) single strand V-belts, the width of which is thirteen thirty-seconds (13⁄32) inch or less.”
Flywheels located so that any part is 7 feet or less above the floor or platform must be guarded by one of the methods 1910.219(b)(1) lists, the first being an enclosure of sheet, perforated or expanded metal, or woven wire.
“Flywheels located so that any part is seven (7) feet or less above floor or platform shall be guarded in accordance with the requirements of this subparagraph: (i) With an enclosure of sheet, perforated, or expanded metal, or woven wire;”
All exposed parts of horizontal shafting 7 feet or less from the floor or working platform, except runways used only for oiling or running adjustments, must be protected by a stationary casing enclosing the shafting completely or by a trough, as location requires.
“All exposed parts of horizontal shafting seven (7) feet or less from floor or working platform, excepting runways used exclusively for oiling, or running adjustments, shall be protected by a stationary casing enclosing shafting completely or by a trough enclosing sides and top or sides and bottom of shafting as location requires.”
Pulleys with any part 7 feet or less from the floor or working platform must be guarded under paragraphs (m) and (o) of 1910.219.
“Pulleys, any parts of which are seven (7) feet or less from the floor or working platform, shall be guarded in accordance with the standards specified in paragraphs (m) and (o) of this section.”
Pulleys with cracks, or with pieces broken out of the rims, must not be used.
“Pulleys with cracks, or pieces broken out of rims, shall not be used.”
Where both runs of a horizontal belt are 7 feet or less from the floor, the guard must extend to at least 15 inches above the belt or to a standard height; where both runs are 42 inches or less from the floor, the belt must be fully enclosed under paragraphs (m) and (o). In powerplants or power-development rooms, a guardrail may be used instead of that guard.
“Where both runs of horizontal belts are seven (7) feet or less from the floor level, the guard shall extend to at least fifteen (15) inches above the belt or to a standard height except that where both runs of a horizontal belt are 42 inches or less from the floor, the belt shall be fully enclosed in accordance with paragraphs (m) and (o) of this section. (ii) In powerplants or power-development rooms, a guardrail may be used in lieu of the guard required by subdivision (i) of this subparagraph.”
All sprocket wheels and chains must be enclosed unless they are more than 7 feet above the floor or platform. Where the drive extends over other machine or working areas, protection against falling must be provided. This does not apply to manually operated sprockets.
“All sprocket wheels and chains shall be enclosed unless they are more than seven (7) feet above the floor or platform. Where the drive extends over other machine or working areas, protection against falling shall be provided. This subparagraph does not apply to manually operated sprockets.”
A guardrail under 1910.219 must be 42 inches high, with a midrail between the top rail and the floor.
“Guardrail shall be forty-two (42) inches in height, with midrail between top rail and floor.”
All power-transmission equipment must be inspected at intervals not exceeding 60 days and kept in good working condition at all times.
“All power-transmission equipment shall be inspected at intervals not exceeding 60 days and be kept in good working condition at all times.”
Regular oilers must wear tight-fitting clothing, and machinery must be oiled when not in motion, wherever possible.
“The regular oilers shall wear tight-fitting clothing. Machinery shall be oiled when not in motion, wherever possible.”
Sources
- eCFR: 29 CFR 1910.212, General requirements for all machines (as of Nov 3, 2026)Checked November 5, 2026
- eCFR: 29 CFR 1910.213, Woodworking machinery requirements (as of Nov 3, 2026)Checked November 5, 2026
- eCFR: 29 CFR 1910.215, Abrasive wheel machinery (as of Nov 3, 2026)Checked November 5, 2026
- eCFR: 29 CFR 1910.217, Mechanical power presses (as of Nov 3, 2026)Checked November 5, 2026
- eCFR: 29 CFR 1910.219, Mechanical power-transmission apparatus (as of Nov 3, 2026)Checked November 5, 2026
Other OSHA General Industry study guides: Walking-working surfaces, Exit routes and emergency planning, Fire protection, Electrical safety, Personal protective equipment, Hazardous materials, Permit-required confined spaces, Lockout/tagout, Welding, cutting and brazing, Electric power generation, transmission and distribution, Powered industrial trucks (forklifts), Materials handling and storage, Bloodborne pathogens, Occupational noise exposure