ISO 3864 specifies international standards for safety signs and markings in workplaces and public facilities. These labels are graphical, to overcome language barriers.[1] The standard is split into four parts:


These are the colours specified in ISO Standard 3864-4 in RAL colour standard.[2]

Meaning RAL Name RAL Number RGB Hex[3] Example of Colour
Warning Signal Yellow 1003 #F9A800
Prohibition/Fire Equipment Signal Red 3001 #9B2423
Mandatory Signal Blue 5005 #005387
Safe Condition Signal Green 6032 #237F52
Backgrounds and Symbol Signal White 9003 #ECECE7
Symbol Signal Black 9004 #2B2B2C

In addition, ISO standard 3864-2:2016 lays out the following colours that correspond to levels of risk.[4] This standard adds "Orange" as an incremental colour to the pallette above.

Meaning Background colour of panel Contrast colour Definition RGB Hex Example of Colour
Low level of risk Yellow Black RAL 1003 [per ISO 3864-4] #F9A800
Medium level of risk Orange Black RAL 2010, Munsell 2,5YR6/14G, or Munsell 5YR6/15G #D05D29
High level of risk Red White RAL 3001 [per ISO 3864-4] #9B2423

Related standards

The corresponding American standard is ANSI Z535. ANSI Z535.1 also explicitly uses multiple levels of hazard, including Yellow (Pantone 109) for 'caution' messages, and Orange (Pantone 151) for stronger 'warning' messages.[5][6][7] Like ISO 3864, ANSI Z535 includes multiple sections: ANSI Z535.6-2006 defines an optional accompanying text in one or more languages.

ISO 3864 is extended by ISO 7010, which provides a set of symbols based on the principles and properties specified in ISO 3864.

See also


  1. ^ ISO 3864-1:2011 from the ISO Catalog
  2. ^ "Sicherheitsfarben – Etikettenwissen".
  3. ^ "RAL Farben | RAL CLASSIC Farben". (in German). Retrieved 2016-05-22.
  4. ^ ""ISO 3864-2:2016 Standard". Retrieved 2021-07-01.
  5. ^ "U.S. Code of Federal Regulations, 49 CFR 172.407". Retrieved 2020-09-28.
  6. ^ "ANSI NEMA Z535". ANSI IBR Standards Portal. American National Standards Institute; National Electrical Manufacturers Association. Retrieved 2020-09-28.
  7. ^ Frantz, J. Paul. "Update of ANSI Standards for Warnings and Future Directions" (PDF). Applied Safety and Ergonomics, Inc. Retrieved 2020-09-28.