Protective Footwear Requirements

Referenced in the Code of Federal Regulations (CFR) Title 29 are the Occupational Safety and Health Administration’s (OSHA's) guidelines for Occupational Foot Protection (1910.136). This regulation refers to the American National Standards Institute (ANSI) American National Standard for Personal Protection - Protective Footwear (ANSI Z41) for its performance criteria.

On March 1, 2005, ANSI Z41 was withdrawn and replaced by two new American Society of Testing Material (ASTM) International Standards. The new ASTM standards are F2412-05 Standard Test Methods for Foot Protection and F2413-05 Standard Specification for Performance Requirements for Foot Protection.

This document provides an overview of the OSHA standard, the ANSI performance criteria and the ASTM performance requirements.

Occupational Foot Protection

According to 1910.136(a), "Each affected employee shall wear protective footwear when working in areas where there is a danger of foot injuries due to falling or rolling objects, or objects piercing the sole, and where such employee's feet are exposed to electrical hazards." Appendix B to subpart I identifies the following occupations for which foot protection should be routinely considered: shipping and receiving clerks, stock clerks, carpenters, electricians, machinists, mechanics and repairers, plumbers, assemblers, drywall installers and lathers, packers, wrappers, craters, punch and stamping press operators, sawyers, welders, laborers, freight handlers, gardeners and grounds keepers, timber cutting and logging workers, stock handlers and warehouse laborers.

Requirements of ANSI Z41

The ANSI Z41 standard defines performance measurements and test methods for protective footwear. Effective with the last revision of this standard, the ANSI Z41-1999 requires suppliers and manufactures of Protective Footwear to have independent laboratory test results available to confirm compliance with the standard. And all protective footwear that is certified as meeting ANSI Z41 must first meet the requirements of Section 1 "General Requirements for All Types of Footwear--Impact and Compression Resistance". Then the requirements of additional sections such as electrical hazard protection, conductive protection and protection against punctures and penetration can be met.

Protective footwear can meet all the requirements of the ANSI standard or specific elements of it, as long as it first meets the requirements for toe protection in Section 1. A work boot that meets the impact and compression requirements of the ANSI standard may not provide protection for metatarsal, electrical or penetration hazards. All footwear manufactured to ANSI specifications will be marked with the specific portion of the standard with which it complies.

The ANSI standard incorporates a coding system that manufacturers use to identify the portions of the standard with which the footwear complies. The identification code must be legible (printed, stamped, stitched, etc.) on one shoe of each pair of protective footwear.

ANSI Z41 PT 99
F I/75 C/75
Mt/75 EH
PR

Line #1: ANSI Z41 PT 99:
This line identifies the ANSI standard. The letters PT indicate the protective toe section of the standard. This is followed by the last two digits of the year of the standard with which the footwear meets compliance (1999).

Line #2: F I/75 C/75:
This line identifies the applicable gender [M (Male) or F (Female)] for which the footwear is intended. It also identifies the existence of impact resistance (I), the impact resistance rating (75, 50 or 30 foot-pounds), compression resistance (C) and the compression resistance rating (75, 50 or 30 which correlates to 2500 pounds, 1750 pounds, and 1000 pounds of compression respectively).

Lines 3 & 4: Mt Cd EH PR & SD:
Lines 3 and 4 are used to reference additional sections in the standard. They are use to designate metatarsal (Mt) resistance and rating, conductive (Cd) properties, electrical hazard (EH), puncture resistance (PR) and static dissipative (SD) properties, if applicable. Line 4 is only used when more than three sections of ANSI Z41 apply.

The purpose of metatarsal footwear is to prevent or reduce the severity of injury to the metatarsal and toe areas. The existence of metatarsal resistance (Mt) and the rating (75, 50 or 30 foot-pounds) is identified.

Conductive (Cd) footwear is intended to protect the wearer in an environment where the accumulation of static electricity on the body is a hazard. It is designed to dissipate state electricity from the body to the ground. The electrical resistance must range between zero and 500,000 ohms.

Electrical hazard (EH) footwear is manufactured with non-conductive electrical shock resistant soles and heals. It is intended to provide a secondary source of protection against accidental contact with live electrical circuits, electrically energized conductors, parts or apparatus. It must be capable of withstanding the application of 14,000 volts at 60 hertz for one minute with no current flow or leakage current in excess of 3.0 milliamperes, under dry conditions.

The purpose of sole puncture resistant (PR) protective footwear is to reduce the possibility of injury caused by sharp objects that may penetrate the soles of the footwear. The puncture resistant device must be an integral part of the footwear and must be constructed into the shoe during the manufacturing process. The footwear must withstand a minimum force of 270 pounds. Devices constructed of metal must pass the corrosion resistance testing and show no sign of corrosion after being exposed to a five percent salt solution for 24-hours. The puncture resistant footwear must show no signs of cracking after being subjected to 1.5 million flexes.

Static dissipative (SD) footwear is designed to reduce the accumulation of excess static electricity by conducting body charge to ground while maintaining a sufficiently high level of resistance. There are two static dissipative classifications – Type I and Type II. Both types have a lower limit of resistance of 10⁶ ohms. Type I footwear’s electrical resistance must not exceed 10⁸ ohms, which is generally considered acceptable for semi-conductor applications. Type II footwear’s electrical resistance must not exceed 10⁹ ohms and has applications in work environments less demanding than Type I.

ASTM F2413-05 Requirements

The ASTM F2413-05 standard covers minimum requirements for the design, performance, testing and classification of protective footwear. Footwear certified as meeting ASTM F2413-05 must first meet the requirements of Section 5.1 “Impact Resistant Footwear” and Section 5.2 “Compression Resistant Footwear”. Then the requirements of additional sections such as metatarsal protection, conductive protection, electric shock protection, static dissipative protection and protection against punctures can be met.

Protective footwear can meet all the requirements of the ASTM standard or specific elements of it, as long as it first meets the requirements for impact and compression resistance. All footwear manufactured to the ASTM specification must be marked with the specific portion of the standard with which it complies. One shoe of each pair must be clearly and legibly marked (stitched in, stamped on, pressure sensitive label, etc.) on either the surface of the tongue, gusset, shaft or quarter lining.

The following is an example of an ASTM marking that may be found on protective footwear:
ASTM F2413-05
M I/75/C/75/Mt75
PR
CS

Line #1: ASTM F2413-05:
This line identifies the ASTM standard – it indicates that the protective footwear meets the performance requirements of ASTM F2413 issued in 2005.

Line #2: M I/75 C/75 Mt75:
This line identifies the gender [M (Male) or F (Female)] of the user. It also identifies the existence of impact resistance (I), the impact resistance rating (75 or 50 foot-pounds), compression resistance (C) and the compression resistance rating (75 or 50 which correlates to 2500 pounds. and 1750 pounds of compression respectively). The metatarsal designation (Mt) and rating (75 or 50 foot-pounds) is also identified.

Lines 3 & 4: PR CS
Lines 3 and 4 are used to identify footwear made to offer protection from other specific types of hazards referenced in the standard. They are use to designate conductive (Cd) properties, electrical insulation properties (EH), footwear designed to reduce the accumulation of excess static electricity (SD), puncture resistance (PR), chain saw cut resistance (CS) and dielectric insulation (DI), if applicable. Line 4 is only used when more than three sections of the ASTM standard apply.

Conductive (Cd) footwear is intended to provide protection for the wearer against hazards that may result from static electricity buildup and to reduce the possibility of ignition of explosives or volatile chemicals. The footwear must facilitate electrical conductivity and the transfer of static electricity build up from the body to the ground. The electrical resistance must range between zero and 500,000 ohms.

Electrical shock resistant (EH) footwear is manufactured with non-conductive electrical shock resistant soles and heals. The outsole is intended to provide a secondary source of electric shock resistance protection to the wearer against the hazards from an incidental contact with live electrical circuits, electrically energized conductors, parts or apparatus. It must be capable of withstanding the application of 14,000 volts at 60 hertz for one minute with no current flow or leakage current in excess of 3.0 milliamperes, under dry conditions.

Static dissipative (SD) footwear is designed to provide protection against hazards that may exist due to excessively low footwear resistance, as well as maintain a sufficiently high level of resistance to reduce the possibility of electric shock. The footwear must have a lower limit of electrical resistance of 10⁶ ohms and an upper limit of 10⁸ ohms.

Puncture resistant (PR) footwear is designed so that a puncture resistant plate is positioned between the insole and outsole. It is an integral and permanent part of the footwear. Devices constructed of metal must pass the ASTM B117 Practice for Operating Salt Spray (Fog Apparatus) corrosion resistance testing. The device must show no sign of corrosion after being exposed to a five percent salt solution for 24-hours. The puncture resistant footwear must show no signs of cracking after being subjected to 1.5 million flexes and have a minimum puncture resistance of 270 pounds.

Chain saw cut resistant (CS) footwear is designed to provide protection to the wearer’s feet when operating a chain saw. It is intended to protect the foot area between the toe and lower leg. This footwear must meet the ASTM F1818 Specification for Foot Protection for Chainsaw Users standard.

Dielectric insulation (DI) footwear is designed to provide additional insulation if accidental contact is made with energized electrical conductors, apparatus or circuits. It must meet the minimum insulation performance requirements of ASTM F1117 (Specification for Dielectric Footwear) and be tested in accordance with ASTM F1116 (Test Method for Determining Dielectric Strength of Dielectric Footwear).

Add-On Devices

An important point to remember is that neither the ANSI nor ASTM standard allows for the use of add-on type devices - strap-on foot, toe or metatarsal guards - as a substitute for protective footwear. According to ANSI Z41 – 2.1.2 "Any protective toe cap or metatarsal guard must be designed, constructed and manufactured into the protective footwear during the manufacturing process and tested as an integral part of the footwear". Per ASTM 5.1.2 “Footwear shall be designed, constructed, and manufactured so that a protective toe cap is an integral and permanent part of the footwear”. Per ASTM 5.3.3 “The metatarsal protection shall be an integral and permanent part of the footwear.

While ANSI and ASTM both exclude add-on devices, it doesn't necessarily mean they're not acceptable to OSHA. This paradox exists because OSHA states under 1910.136(b) that the footwear shall comply with ANSI or shall be demonstrated by the employer to be equally effective. This means that if an employer can provide documentation, such as testing data proving their add-on devices provide protection equivalent to ANSI performance standards, then the add-on devices are acceptable to OSHA. Most manufacturers of add-on devices have submitted their products to independent laboratories for testing. This data and its results can be obtained upon request.

Sources for More Information

OSHA 29 CFR 1910.132
Personal Protective Equipment – General Requirements

OSHA 29 CFR 1910.136
Personal Protective Equipment – Occupational Foot Protection

ASTM B117
Practice for Operating Salt Spray (Fog) Apparatus

ASTM F1116
Test Method for Determining Dielectric Strength of Dielectric Footwear

ASTM F1117
Specification for Dielectric Footwear

ASTM F1818
Specification for Foot Protection for Chainsaw Users

ASTM F2412-05
Standard Test Methods for Foot Protection

ASTM F2413-05
Standard Specification for Performance Requirements for Foot Protection