The importance of safety signs cannot be overstated. It’s impossible to know how many lives workplace safety signs save per year, but people take notice when there isn’t a sign posted where one ought to be. Thanks to the Occupational Safety and Health Administration (OSHA), workers as well as the public at-large have come to expect the ever-present safety signs posted around industrial job sites. Through OSHA compliance, the resulting uniformity makes safety signs easy to understand, which is what makes them effective.

Hard Hat Area Sign

What is OSHA?

After President Richard Nixon signed the Occupational Safety and Health Act into law in 1971, OSHA was established as an agency in the U.S. Department of Labor. The agency is charged with enforcing workplace safety laws. OSHA also has regulatory powers, and they have created guidelines for a number of workplace safety processes and procedures.

There are OSHA regulations pertaining specifically to the design of OSHA safety signs. The regulations describe types of safety signs, and they also point to a set of design standards created by the American National Standards Institute (ANSI) in the late 1960s. The ANSI standards have actually been updated since then, but as with the nature of governmental bureaucracy, they have not gone through the necessary approval process within OSHA to become official yet. Still, OSHA will make exceptions during their inspections if signs are up to the new ANSI standards, and still offer at least as much warning as they would under the official ANSI standards from the late 1960s that are recognized by OSHA.

What are the OSHA safety sign requirements?

What set of regulations would be complete without a definition of a basic word for which everyone takes for granted? In this case, the word is “sign”. OSHA defines a sign as a surface that contains warnings or instructions about nearby hazards for workers and the public at-large. OSHA specifically points out that news releases, safety posters and bulletins are not included in the definition of safety sign. In other words, having a safety poster won’t help a business become OSHA compliant. Where there are hazards, there needs to be safety signs warning of those hazards.

According to OSHA regulations, there are basically three different types of workplace safety signs. They are danger signs, caution signs and informational signs. To be OSHA compliant, a safety sign needs to conform to a specific set of colors which are dictated by on the type of sign being displayed. To simply describe the basic layout of a safety sign, it should be rectangular, consisting of a background, a colored panel at the top containing a signal word, and then an area for a message below it.

Danger signs

Danger signs should be used to signify an imminent threat such as radiation present in an area.  The OSHA regulations say there may be no variations made to their symbols and messaging as directed by the standards. A danger sign needs to specify that there is an immediate danger, and employees need to be trained to recognize that threat and act appropriately.

Danger signs need to be red, black and white as described in both the ANSI and OSHA standards.The sign background should be white and the panel at the top of the sign should be black.In the black panel, the word “Danger” should be white letters in a red circle. Any letters that appear on the white background should be black. Following these guidelines will make a danger sign OSHA compliant.

Warning signs

Warning signs should be used to warn against a potential hazard that could cause injury or death such as “Hot Surface”.  The OSHA regulations say there may be no variations made to their symbols and messaging as directed by the standards. A warning sign needs to specify that there is a potential danger, and employees need to be trained to recognize that dangerous condition and act appropriately.

Warning signs need to have an orange background with black lettering as described in both the ANSI and OSHA standards.  The panel at the top of the sign should be the black warning symbol.  In the black panel, the word “Warning” should be black letters in a horizontal rectangle. Any letters that appear on the orange background should be black. Following these guidelines will make a danger sign OSHA compliant.

Caution signs

Caution signs are used to warn of potentially hazardous situation or to caution against unsafe practices or inappropriate actions that could cause injury or death. One example may be a sign that says “Hard Hat Area” or “Watch for Forklifts”.  According to the OSHA rules about safety signs, employees need to be trained that these signs indicate that they need to take proper precautions while in that area to ensure safety and prevent accidents.

The ANSI standards for caution signs say they need to have a yellow background. Like danger signs, caution signs should also have a black panel up top. However, caution panels should have yellow letters for the word “caution” to comply with OSHA standards. Any letters appearing in the message below the panel will be on the yellow background and should be black.

Informational signs

Informational signs follow a similar uniformity as danger and caution signs, except info sign colors are white backgrounds with a green panel and white letters within the panel. Below the panel, the lettering on the white background of informational signs should be black to comply with ANSI standards.

Letters and Symbols

When it comes to lettering for safety signs, the information in the OSHA standards gives readability guidelines for letters ranging from 3.5 inches to a quarter-inch tall. Letters 3.5 inches tall are visible up to 200 to 210 feet away. One-inch letters can be read 60 to 65 feet away, and quarter-inch letters are visible from 15 to 20 feet.

ANSI Regulations

The OSHA standards for safety signs have yet to be updated. They cite standards created by ANSI from 1967 and 1968 currently; however there are new ANSI standards since 2011 governing signs. As long as protection offered by signs is equal to or greater than 2011 standards, then you should be covered when they’re formally accepted. Still, the new ANSI standards have not been formally adopted, and enforcement will still be based on the old ANSI standards.

The old standards for safety signs were found under ANSI Z35.1-1968 and ANSI Z53.1-1967. These sets of standards covered sign specifications and colors respectively. Today, ANSI has a number of standards to govern safety signs. The new standards are labeled as the ANSI Z535 standards. However, as mentioned above, the new standards have yet to officially become part of OSHA regulations.

Safety Signs & OSHA Compliance

Ultimately, the most important thing about safety signs is that they work. Safety signs must be uniform in design and easy-to-read while maintaining a concise message. OSHA standards say safety signs need enough necessary info to be understood. People should know at a glance what they should and shouldn’t do in an area. It’s easy to accomplish this if employers and sign makers maintain OSHA compliance on safety signs.


U.S. Department of Labor. (N.D.). “Specifications for accident prevention signs and tags.” OSHA. Retrieved from

U.S. Department of Labor. (22 February 2011). “Standard Interpretations” OSHA. Retrieved from

United States of America Standards Institute. (1968). “Specifications for Accident Prevention Signs.” Z53.1-1968. Retrieved from