Moving machine parts have the potential to cause severe workplace injuries, such as crushed fingers or hands, amputations, burns, or blindness. Safeguards are essential for protecting workers from these preventable injuries. Any machine part, function, or process that may cause injury must be safeguarded. When the operation of a machine or accidental contact injure the operator or others in the vicinity, the hazards must be eliminated or controlled. This page contains general information on the various hazards of mechanical motion and techniques for protecting workers.

Machine guarding hazards are addressed in specific standards for the general industry, marine terminals, longshoring, and the construction and agriculture industries.

Standards

This section highlights OSHA standards, Federal Registers (rules, proposed rules, and notices), directives (instructions for compliance officers), standard interpretations (official letters of interpretation of the standards), and national consensus standards related to machine guarding.

OSHA

Note: Twenty-five states, Puerto Rico and the Virgin Islands have OSHA-approved State Plans and have adopted their own standards and enforcement policies. For the most part, these States adopt standards that are identical to Federal OSHA. However, some States have adopted different standards applicable to this topic or may have different enforcement policies.

General Industry (29 CFR 1910)

• 1910 Subpart O, Machinery and machine guarding. Includes definitions, general requirements, and different kinds of machinery requirements.
  • 1910.211, Definitions
  • 1910.212, General requirements for all machines
  • 1910.213, Woodworking machinery requirements
  • 1910.214, Cooperage machinery [Reserved]
  • 1910.215, Abrasive wheel machinery
  • 1910.216, Mills and calendars in the rubber and plastics industries
  • 1910.217, Mechanical power presses. Includes general requirements in addition to specific requirements for construction, safeguarding, dies, inspection, maintenance, modification, operation, injury reporting, and presence sensing device initiation (PSDI).
  • Appendix A, Mandatory requirements for certification/validation of safety systems for presence sensing device initiation of mechanical power presses
  • Appendix B, Nonmandatory guidelines for certification/validation of safety systems for presence sensing device initiation of mechanical power presses
  • Appendix C, Mandatory requirements for OSHA recognition of third-party validation organizations for the PSDI standard
  • Appendix D, Nonmandatory supplementary information
  • 1910.218, Forging machines
  • 1910.219, Mechanical power-transmission apparatus
• 1910 Subpart R, Special industries
• 1910.262, Textiles. Paragraph (c)(3) [reserved] contains a short statement on machine guarding requirements and a reference to 29 CFR 1910.219. [related topic page]
• 1910.263, Bakery equipment. Paragraph (c) addresses general requirements for machine guarding.
• 1910.268, Telecommunications. Paragraph (b)(1)(v) addresses some general requirements for machine guarding.

Marine Terminals (29 CFR 1917)

• 1917 Subpart G, Related terminal operations and equipment
• 1917.151, Machine guarding

Longshoring (29 CFR 1918)

• 1918 Subpart I, General working conditions
• 1918.96, Maintenance and repair work in the vicinity of longshoring operations. Paragraph (e) contains general requirements for machine guarding (see also 29 CFR 1918.2, definition of "danger zone").

Construction Industry (29 CFR 1926)

• 1926 Subpart I, Tools - Hand and power. Includes general machine guarding requirements and specific guarding requirements for different types of tools.
  • 1926.300, General requirements
  • 1926.301, Hand tools
  • 1926.302, Power-operated hand tools
  • 1926.303, Abrasive wheels and tools
  • 1926.304, Woodworking tools
  • 1926.305, Jacks-lever and ratchet, screw, and hydraulic
  • 1926.306, Air receivers
  • 1926.307, Mechanical power-transmission apparatus

Agriculture Industry (29 CFR 1928)

• 1928 Subpart D, Safety for agricultural equipment
• 1928.57, Guarding of farm field equipment, farmstead equipment, and cotton gins

Federal Registers

• Mechanical Power -- Transmission Apparatus; Mechanical Power Presses; Telecommunications; Hydrogen. Final Rules 69:31880-31882, (2004, June 8). Corrects errors in four OSHA standards:
  1. The first correction deletes two references to a nonexisting table in the Mechanical Power-Transmission Apparatus Standard.
  2. The second is a correction of typographical errors in the Mechanical Power Presses Standard.
  3. The third correction is to a cross-reference in the Telecommunications Standard.
  4. The fourth correction is to a reference to a table contained in the Hazardous Materials Standard for Hydrogen.
• Notice of Availability of the Regulatory Flexibility Act Review of Presence Sensing Device Initiation for Mechanical Power Presses. Proposed Rules 69:31927-31929, (2004, June 8). OSHA has conducted a review of the Presence Sensing Device Initiation (PSDI) requirements of the Mechanical Power Presses Standard pursuant to section 610 of the Regulatory Flexibility Act, and section 5 of Executive Order 12866 on Regulatory Planning and Review. Based on this review and public comments, OSHA has decided to update its mechanical power press standard to ANSI B.11.1-2001
  


• Mechanical Power Presses. Final Rules 53:8322-65, (1988, March 14). Amendment of the standard for mechanical power presses, 29 CFR 1910.217, to allow (but not require) presence sensing device initiation (PSDI) on certain types of power presses.
  


• Search all available Federal Registers.

Directives

• National Emphasis Program on Amputations. CPL 03-00-003, (2006, October 27). Describes policies and procedures for implementing a National Emphasis Program (NEP) to identify and reduce or eliminate the workplace incidence of hazards which are causing or are likely to cause amputations.
  


• Guidelines for Point of Operation Guarding of Power Press Brakes. CPL 02-01-025 [CPL 2-1.25], (1997, February 14). Provides guidelines for compliance officers who determine compliance with the guarding requirements for power press brakes. Describes when guarding by "safe distance" is permitted.
  


• Abrasive Operation Using Cutoff Wheels and Masonry Saws. STD 01-12-026 [STD 1-12.26A], (1994, September 26). Provides guidelines for violations related to guards for cutoff wheels and masonry saws.
  


• Awareness Barriers Installed on Metal Cutting Shears. STD 01-12-025 [STD 1-12.25A], (1994, July 12). Provides guidance for applying awareness barrier safeguards as installed on metal cutting shears.
  


• Guarding of Three-Roller Printing Ink Mills. STD 01-12-023 [STD 1-12.23A], (1994, July 12). Clarifies the guarding requirements of 29 CFR 1910.212 relative to the ingoing nip point on three-roller printing ink mills and to assure uniformity in the enforcement of the standard nationally.
  


• Alternative Abatement Methods of 29 CFR 1910.212(a)(1) and (a)(2) As Applied to the Oil and Gas Drilling Industry. STD 01-12-028 [STD 1-12.28], (1983, February 7). Provides guidelines for the use of certain monitoring techniques to comply with  29 CFR 1910.212(a)(1) and (a)(2) in the oil and gas drilling industry.
  


• Portable Belt Sanding Machines as Covered by 29 CFR 1910.243(a)(3) and 29 CFR 1926.304(f). STD 01-13-004 [STD 1-13.4], (1981, August 5). Provides guidance to allow equitable enforcement of 29 CFR 1910.243(a)(3) and 29 CFR 1926.304(f) as they pertain to the guarding of portable belt sanders.
  


• 29 CFR 1910.212(a)(3)(ii), Point of Operation Guarding for All Machines as Applied to the Hand-Fed Engraving Presses Used in the Engraved Stationery Manufacturing Industry. STD 01-12-022 [STD 1-12.22], (1979, January 2). Provides guidance in applying point of operation guarding requirements relative to hand-fed engraving presses in the engraved stationery industry, when using the face down method of printing.
  


• Defining Acceptable Guarding of Fan Blades. STD 01-12-001 [STD 1-12.1], (1978, October 30). Clarifies the applicability of 29 CFR 1910.212(a)(5) and directs answers to inquiries.
  


• Reduction of Air Pressure below 30 psi for Cleaning Purposes. STD 01-13-001 [STD 1-13.1], (1978, October 30). Includes requirements for chip guarding.
  


• Caution Labeling of Radial Saws: 29 CFR 1910.213(h)(5). STD 01-12-004 [STD 1-12.4], (1978, October 30). Provides guidance in the enforcement of the subject provision.
  


• Acceptable Guarding for Circular Meat Cutting Saws: 29 CFR Section 1910.212(a)(3)(ii). STD 01-12-005 [STD 1-12.5], (1978, October 30). Provides guidance on the acceptable methods for guarding meat cutting saws.
  


• 29 CFR 1910.218 Forging Machines. STD 01-12-006 [STD 1-12.6], (1978, October 30). Clarifies appropriate enforcement of 29 CFR 1910.218.
  


• 29 CFR 1910.217 and 29 CFR 1910.212; Applicability of Platen Presses. STD 01-12-007 [STD 1-12.7], (1978, October 30). Provides specific clarifications on the applicability of 29 CFR 1910.217 and 29 CFR 1910.212 to platen presses.
  


• 29 CFR 1910.215(a)(4), Abrasive Wheel Machinery Work Rests. STD 01-12-008 [STD 1-12.8], (1978, October 30). Provides clarification on the acceptable methods for the use of work rests.
  


• 29 CFR 1910.212 General Requirements for all Machines. STD 01-12-009 [STD 1-12.9], (1978, October 30). Clarifies the intent of 29 CFR 1910.212 as applied to blade guards for chain saws. 
  


• Application of 29 CFR 1910.212(a)(1) to Food Waste Disposal Equipment. STD 01-12-010 [STD 1-12.10], (1978, October 30). Assures uniformity in the application of 29 CFR 1910.212 to point of operation guarding on food waste disposal equipment.
  


• Clarification of 29 CFR 1910.219, the Terms "Enclosed" and "Fully Enclosed", as applying to Power Transmission Belts. STD 01-12-014 [STD 1-12.14], (1978, October 30). Provides clarification of the application of "enclosed" and "fully enclosed" as applying to power transmission belts, and guarding by location.
  


• 29 CFR 1910.213(a)(4), Woodworking Machinery Requirements. STD 01-12-015 [STD 1-12.15], (1978, October 30). Provides guidance to the field on the applicability of 29 CFR 1910.213(a)(4) in protecting employees from automatic cut-off saws that stroke continuously without the operator being able to control each stroke.
  


• 29 CFR 1910.213(h)(1), Radial Saw Guards. STD 01-12-017 [STD 1-12.17], (1978, October 30). Provides clarification on the applicability of 29 CFR 1910.213 as it relates to the saw mill industries.
  


• 29 CFR 1910.213(c)(l) and (h)(1), Woodworking Machinery Guarding Requirements. STD 01-12-018 [STD 1-12.18], (1978, October 30). Specifies requirements for hand-fed ripsaws and swing cutoff saws and radial saws.
  


• Application 1910.212(a)(1) to Sewing Machines in the Light Apparel Manufacturing Industries. STD 01-12-019 [STD 1-12.19], (1978, October 30). Provides a uniform means of evaluating the nip point and moving belt hazard on light and medium duty sewing machines such as those used in apparel manufacturing and sewing of light weight materials.
  


• 29 CFR 1910.217(b)(3)(i), Mechanical Power Presses Single Stroke Mechanism Requirements. STD 01-12-020 [STD 1-12.20], (1978, October 30). Provides an interpretation of 29 CFR 1910.217(b)(3)(i) and guidance for field personnel for the requirement of single stroke mechanisms on full revolution type mechanical power presses.
  


• 29 CFR 1910.217 Mechanical Power Presses, Clarifications. STD 01-12-021 [STD 1-12.21], (1978, October 30). Provides a guide to aid in the recognition of mechanical power presses' point of operation hazards and uniform clarifications of definitions, guards, develop and methods of safeguarding.
  


• Search all available directives.

Standard Interpretations

• Use of laser guarding systems with hydraulic press brakes. (2004, February 11).
  


• Maximum permissible guard openings for blade guards on cooling fans. (2003, August 21).
  


• Questions and answers about color coding machine and machine guards according to ANSI Z535.1-1990. (2003, August 19).
  


• OSHA machine guarding standards and the ISO/IEC standards adopted under the GATT; National Emphasis Program on Amputations. (2003, May 13).
  


• Standards that apply to cotton gins. (2002, August 6).
  


• Request for guidance on saws operated on "cut-climb/reverse-rotation" mode. (2002, July 12).
  


• Flexible corrugated plastic covers for temporary use to cover live electric parts in switch and panel boxes. (2002, June 17).
  


• Guarding/hazards of using woodcutting sawblades on a cut-off machine. (1999, November 15).
  


• Multiple interpretations regarding mechanical power presses. (1998, May 8).
  


• Machine-guarding requirements. (1994, December 20). Includes a request for a permanent variance from 29 CFR 1910.212(a)(1), the standard which defines OSHA's general machine-guarding requirements.
  


• Presence sensing devices (PSDs) for power presses. (1994, August 11).
  


• Applicability of the Machine Guarding and Lockout/Tagout standards to printing presses. (1993, June 14). 
  


• Printing Presses: requirements for normal production and servicing operations. (1992, September 16).
  


• Search all available standard interpretations.

National Consensus

Note: These are NOT OSHA regulations. However, they do provide guidance from their originating organizations related to worker protection.

American National Standards Institute (ANSI)

• ANSI B11 Subcommittees. The ANSI B11 committee is responsible for developing machine tool safety standards. This document provides brief descriptions of the subcommittees and the hazards they are addressing.
  • B11.1-2001, Safety Requirements for Mechanical Power Presses
  • B11.2-1995 (R05), Hydraulic Power Presses - Safety Requirements for Construction, Care, and Use
  • B11.3-2002, Safety Requirements for Power Press Brakes
  • B11.4-2003, Safety Requirements for Shears
  • B11.5-1988 (R05), Ironworkers - Safety Requirements for Construction, Care, and Use
  • B11.6-2001, Safety Requirements for Manual Turning Machines with or without Automatic Control
  • B11.7-1995 (R05), Cold Headers & Cold Formers - Safety Requirements for Construction, Care, and Use
  • B11.8-2001, Safety Requirements for Manual Milling, Drilling, & Boring Machines with or without Automatic Control
  • B11.9-1975 (R05), Safety Requirements for the Construction, Care, and Use of Grinding Machines
  • B11.10-2003, Safety Requirements for Metal Sawing Machines
  • B11.11-2001, Safety Requirements for Gear and Spline Cutting Machines
  • B11.12-2005, Safety Requirements for Roll Forming & Roll Bending Machines
  • B11.13-1992 (R98), Single and Multiple-Spindle Automatic Bar, and Chucking Machines - Safety Requirements for Construction, Care, and Use
  • B11.14-1996, Coil Slitting Machines - Safety Requirements for Construction, Care, and Use
  • B11.15-2001, Safety Requirements for Pipe, Tube and Shape Bending Machines
  • B11.16-2003 (MPIF #47), Safety Requirements for Powder/Metal Compacting Presses
  • B11.17-2004, Safety Requirements for Horizontal Hydraulic Extrusion Presses
  • B11.18-1997, Safety Requirements for Machines and Machinery Systems for Processing or Slitting or Non-Coiled Metal Strip, Sheet or Plate
  • B11.19-2003, Performance Criteria for Safeguarding
  • B11.20-2004, Safety Requirements for Integrated Manufacturing Systems
  • B11.21-1997, Safety Requirements for Machine Tools Using Lasers For Processing Materials
  • B11.22-2002, Safety Requirements for Turning Centers and Automatic Numerically Controlled Turning Machines
  • B11.23-2002, Safety Requirements for Machining Centers and Automatic Numerically Controlled Milling, Drilling and Boring Machines
  • B11.24-2002, Safety Requirements for Transfer Machines
  • B11.TR 1-2004, Ergonomic Guidelines for the Design, Installation
    And Use of Machine Tools
  • B11.TR 2-1997, Mist Control Considerations for the Design, Installation
    And Use of Machine Tools Using Metalworking Fluids
  • B11.TR 3-2000, Risk Assessment and Risk Reduction- A Guideline to Estimate, Evaluate and Reduce Risks Associated with Machine Tools
  • B11.TR 4-2004, Selection of Programmable Electronic Systems (PES/PLC) for Machine Tools
  • B11.TR5-200X, Sound Level Measurement Guidelines (not an approved document; in development)
  • B11.TR6-200X, Control Reliable Circuits and Servo Drive Technology

Hazard Recognition

The following references aid in recognizing hazards from ineffective machine guarding.

• Machine Guarding. OSHA eTool. Focuses on recognizing and controlling common amputation hazards associated with the operation and use of certain types of machines.
  • Machine Guarding: Horizontal Injection Molding Machines - Interactive Safety Tour. Allows user to take a virtual tour of an injection molding machine.
    
• Amputations [157 KB PDF^*, 2 pages]. OSHA Fact Sheet, (2002). Provides a general overview of amputations in the workplace.
  


• Potential Hazards Associated with the Use of Replacement Materials for Machine Guarding. OSHA Hazard Information Bulletin (HIB). Also available as a 14 KB PDF, 2 pages. Clarifies that replacement machine guard windows must meet or exceed the manufacturer's original design specifications.
  


• 29 CFR 1910.217(g) Mechanical Power Press Point of Operation Injury Reports: 8/1994-12/2000. OSHA. Summarizes "point of operation" injuries from mechanical power presses.
  


• Electrical. OSHA Safety and Health Topics Page.
  


• ANSI B11 Subcommittees. Provides brief descriptions of the subcommittees and the hazards they are addressing. The American National Standards Institute's (ANSI) B11 committee is responsible for developing machine tool safety standards. Additional information about ANSI standards is available on their website.
  


• Injuries and Amputations Resulting from Work with Mechanical Power Presses. US Department of Health and Human Services (DHHS),  National Institute for Occupational Safety and Health (NIOSH) Publication No. 87-107, (1987, March). Describes the hazards of mechanical power presses and provides safety recommendations.
  


• Machine Safety. National Institute for Occupational Safety and Health (NIOSH) Workplace Safety and Health Topic. Links to several documents that discuss machinery safety for different types of agricultural equipment, and machine guarding in general.

Possible Solutions

The following references provide possible solutions for machine guarding hazards.

• Machine Guarding. OSHA eTool. Focuses on recognizing and controlling common amputation hazards associated with the operation and use of certain types of machines.
  • Machine Guarding: Horizontal Injection Molding Machine Safety Tour. Allows user to take a virtual tour of an injection molding machine.
    
• Safeguarding Equipment and Protecting Workers from Amputations. OSHA Publication 3170-02R, (2007). Also available as a 1 MB PDF, 60 pages. Provides information to help identify and manage common amputation hazards associated with operating and using stationary equipment.
  


• Preventing Scalping and Other Severe Injuries from Farm Machinery. US Department  of Health and Human Services (DHHS), National Institute for Occupational Safety and Health (NIOSH) Publication No. 94-105, (1994, June). Describes five cases of persons who were scalped when their hair became entangled around the inadequately guarded rotating drivelines or shafts of farm machinery driven by power take-offs (PTOs).
  


• Concepts and Techniques of Machine Safeguarding. OSHA Publication 3067, (Revised 1992). Covers nearly all aspects of machine guarding, and includes chapters on safeguarding, guard construction, machinery maintenance and repair, and an evaluation checklist.
  


• A Guide for Protecting Workers from Woodworking Hazards. OSHA Publication 3157, (1999). Also available as a 554 KB PDF, 74 pages. Provides a general, non-exhaustive overview of woodworking standard related topics.
  


• OSHA Technical Manual (OTM). OSHA Directive TED 01-00-015 [TED 1-0.15A], (1999, January 20).
  
  • Industrial Robots and Robot System Safety. Section V entitled "Control and Safeguarding Personnel" outlines specific means for safeguarding robot systems.
• NIOSH Leads Evaluation of Strategic Machine Safety Guideline. National Institute for Occupational Safety and Health (NIOSH) Update, (2003, March 3). Contains a notification of a project being led by NIOSH to evaluate the effectiveness of an American National Standards Institute (ANSI) voluntary guideline to prevent fatal injuries from machine contact. 
  
  
• Machine Safeguarding [156 KB PDF, 12 pages]. Environment, Safety, and Health (ES&H), Stanford Linear Accelerator Center (SLAC), Environment, Safety, and Health Division, (2006, October 9). Provides a general discussion of machine hazards and proper safeguarding techniques.
  


• Guideline for Safeguarding Machinery and Equipment [3 MB PDF, 107 pages]. Government of Manitoba, Workplace Safety and Health Branch. Includes basics of machine safeguarding, methods of machine safeguarding, and guard construction.
  


• Preventing Farm Machine Hazards [204 KB PDF, 3 pages]. Ohio State University Extension Fact Sheet AEX-593-91. Discusses hazards associated with farm machinery and the importance of guarding.

Additional Information

Related Safety and Health Topics Pages

• Robotics

Training

• OSHA Training Institute Course Catalog Search. Provides a keyword search and catalog listing of available courses.
  
• Checklist for Abrasive Wheel Equipment Grinders. OSHA, (1999).
  • A Partial List of Accidents Involving Grinders
• Machine Guarding [3 MB ZIP^*]. OSHA. Designed to assist trainers conducting OSHA 10-hour General Industry outreach training for workers. Since workers are the target audience, the material emphasizes hazard identification, avoidance, and control — not standards. No attempt has been made to treat the topic exhaustively.

Other Resources

• Association for Manufacturing Technology (AMT). Accredited Standards Developing Organization (SDO) for the ANSI B11 series of standards for machine tools.
  


• Online Safety Library: Machine Guarding/Machine Shop Safety. Oklahoma State University (OSU), Environmental Health and Safety.

Accessibility Assistance: Contact the OSHA Directorate of Technical Support and Emergency Management at (202) 693-2300 for assistance accessing PDF and ZIP materials.

^*These files are provided for downloading.