⇐ Return to list of articles

ANSI and NEMA Z535 American National Standard For Safety Alerting Standards

ANSI, NEMA, SAS, z535... what does it all mean? Learn more about ANSI and NEMA z535 standards.

There have been many inconsistencies among safety labels and signs. Many different signs and labels addressed the same hazard, but looked completely different due to variations in color, symbol design, layout, and signal words. Safety information is critical information. Color variations in safety labeling and signs can lead to confusion as to the extent of the potential hazard risk. Variations in print layout can lead to safety signs and labels that are difficult to read and variations in the design and formatting can lead to confusion and misunderstanding.

Safety signs and labels contain critical information that needs to be understood quickly and accurately. ANSI Z535 Standards provide a uniform method and systematic approach for the design of safety signs, labels, tags, and barricade tapes, as well as safety messages in collateral materials such as product instruction manuals. Consistent and clear safety labels and signs increase recognition and understanding of critical safety information, which helps to prevent accidents, injuries and deaths, as well as decreasing property damage.

ANSI/NEMA Z535 - American National Standard for Safety Alerting Standards

ANSI/NEMA Z535 the American National Standard for Safety Alerting Standards is published by the National Electrical Manufacturers Association (NEMA) and accredited by the American National Standards Institute (ANSI). ANSI Z535 is a consensus standard addressing design, application and use of safety signs, symbols, and colors. The basic mission of ANSI Z535 is to "develop, refine, and promote a single, uniform graphic system used for communicating safety and accident prevention information". ANSI Z535 addresses how to communicate important safety-related information. The scope of ANSI Z535 is to "develop standards for the design, application, and use of signs, colors, and symbols intended to identify and warn against specific hazards and for other accident prevention purposes".

In the early 70's, OSHA recognized safety signs and safety labels play an important role in safety management, and incorporated ANSI Z53 Standard on Safety Colors, and ANSI Z35 Standard on Safety Signs into OSHA requirements. The history of ANSI Z535 began in 1979 with the forming of the ANSI Z535 Committee on Safety Signs and Colors by combining the ANSI Z35 committee on Safety Signs together with the ANSI Z53 committee on Safety Colors. This new committee developed ANSI Z535.

"Duty to warn" obligations were increasingly evident, leading to greater understanding that liability issues could arise if adequate warnings were not provided. This supported the importance of the creation of ANSI Z535, the uniform visual system for the communication of safety information. However, as the development process proceeded, it was apparent that one standard could not serve all applications acceptably. This lead to the development of two distinct standards, one for workplace applications – ANSI Z535.2, and one or product safety application – ANSI Z535.4.


The ANSI/NEMA Z535 SET of standards, which includes Z535. 1 thru 6, relate to the design, application and use of safety signs, colors and symbols. The standards in the ANSI Z535 Set each have a specific area of focus, yet must harmonize with each other. ANSI Z535 standards were first available in 1992, with standards Z535.1 through .5. ANSI Z535.6 was added in 2006. The most recent revision of the ANSI Z535 Set was published September 15, 2011.

2011 ANSI/NEMA Z535 SET revises the 2006 ANSI Z535 SERIES. This comprehensive collection consists of six standards and a safety color chart. These safety alerting standards work together to provide the information needed to aid in the prevention of accidents, injuries and death by alerting workers and others to potential hazards in the workplace and other places through the use of safety symbols, colors and signs.

The ANSI/NEMA Z535 SET includes two 'foundation standards' which address issues such as the design of safety symbols and color specifications, and apply to the 'application' standards. The other four are 'application standards' offering guidance on applying the safety alerting standards to different types of usage applications.

The ANSI/NEMA Z535 Set also includes four 'foundation standards' which are:

ANSI Z535.1 - Safety Colors This standard identifies the specific shades of colors to be used for safety communication, including the technical definitions, color standards and color tolerances for each of the uniform safety colors. This standard is important for anyone who prints or manufactures safety signs and labels.

ANSI Z535.3 - Criteria for Safety Symbols This standard provides guidelines and criteria for the design, evaluation, and the use of safety symbols for identification and hazard warning to aid in the avoidance of personal injury. The 2011 edition of ANSI Z535.3 brings changes to the method of evaluating the effectiveness of warning symbols to assure there is clear communication of the intended message.

The 'application standards' are:

ANSI Z535.2 – Environmental Facility and Safety Signs This standard addresses the use of a consistent visual layout for the design, application, and use of safety signs in the workplace and in public spaces. The 2011 edition of this standard improves the description of the five types of safety signs used in facilities and is revised to better harmonize with ANSI Z535.4, ANSI Z535.5, and ANSI Z535.6. ANSI Z535.4 – Product Safety Signs and Labels This standard establishes specifications for the design, application, use, and placement of safety signs and labels on varied products for the purpose of product safety and liability prevention. The "safety instruction sign," was added to join the existing types of signs, hazard alerting signs, and safety notice signs, which were more clearly named and defined and named in the 2011 edition. The 2011 edition also more clearly defined 'harm', 'accident', and 'incident' to show the separation between physical injury and other safety-related issues such as property damage.

ANSI Z535.5 – Safety Tags and Barricade Tapes (for Temporary Hazards) This standard addresses safety tags and barricade tapes, for use only until the identified hazard is eliminated or the hazardous operation is finished, and provides guidance on the construction and use of the safety tags and barricade tape. In the 2011 edition the use of a "Safety Instructions" tag was added. The 2011 edition more clearly defined and named the existing types of signs, hazard alerting tags and barricade tapes, and safety notice tags and barricade tapes.

ANSI Z535.6 - Product Safety Information in Product Manuals, Instructions and Other Collateral Materials This standard was first published in 2006 and provides guidance on presenting safety information messages in printed materials for products and other collateral materials. This standard promotes the efficient development of safety messages and helps to improve the safety of products while reducing accidents and personal injury as well as product liability lawsuits.

With the 2011 edition of ANSI/NEMA Z535 there were two major changes that applied to all of the four application standards. These changes in the 2011 edition included:

"Safety Instruction" Tag The 2011 edition of ANSI Z535 includes the addition of the use of a "safety instruction" tag, which is a new type of safety sign. This sign does not warn of a specific hazard. It described the instructions or procedures that are related to safety issues. An example of a "safety instruction" sign would be emergency shutdown instructions for equipment in a facility. "Safety Instruction" signs have specific color requirements, with "safety white" lettering on a "safety green" background.

Warning Definitions: The second change addresses warning definitions, with improvement to more clearly show the separation between the risks from hazards that may result in physical injury or death, compared to risks from hazards that are unrelated to personal injury, such as property damage.

ANSI Z535 SAFETY COLOR CHART The ANSI/NEMA Z535 SET also includes the ANSI Z535 SAFETY COLOR CHART color chart showing the color specifications .

ANSI Z535 does not determine when a safety sign, safety label or safety message must be used, rather, when there is a need for a safety sign, safety label, or safety message, ANSI Z535 provides guidance on designing those signs, labels and messages so they are consistent and easily readable, and have maximum recognition and understanding. ANSI Z535 standards help to determine the proper visual layout, the proper use of signal words, correct colors, appropriate print layout and style. The signal word and colors should match correctly with the risk level of the potential safety hazard.

Although mainly used in the US, ongoing work is being done to harmonize ANSI Z535 with the corresponding global ISO standards.

Tags: ANSI NEMA standards, ANSI z535, SAS, NEMA z535