Hazard symbols are universally recognized symbols designed to alert individuals to the presence
of hazardous or dangerous materials, locations, or conditions. These include risks associated
with electromagnetic fields, electric currents, toxic chemicals, explosive substances, and radioactive
materials. Their design and use are often governed by laws and standards organizations to ensure
clarity and consistency. Hazard symbols may vary in color, background, borders, or accompanying text
to indicate specific dangers and levels of risk, such as toxicity classes. These symbols provide a quick,
universally understandable visual warning that transcends language barriers, making them more
effective than text-based warnings in many situations.
List of Standardized Hazard Symbol Systems
[edit]
                      Warnin
 Standard                        Scope                            Audience                  State
                      g
 ISO 7010 warning                General purpose warning                                    Currently
                                                                  The general public
 symbols                         symbols                                                    used
                                 The labelling of containers
                                                                  The general public, the
                                 and for workplace hazard
 GHS hazard                                                       workplace, and            Currently
                                 warnings, and for use during
 pictograms                                                       material transport        used
                                 the transport of dangerous
                                                                  personnel
                                 goods
                                 To quickly and easily identify                             Currently
 NFPA 704 Safety                                                  Emergency response
                                 the risks posed by hazardous                               used in the
 Square                                                           personnel
                                 materials                                                  US
 Hazardous                       A numerical hazard rating        Employers and workers
                                                                                            Currently
 Materials                       used to identify the risks       who handle and are
                                                                                            used in the
 Identification                  posed by hazardous               exposed to hazardous
                                                                                            US
 System                          materials                        chemicals
                                                                  Mixtures of chemicals
 EU Directive                    The labelling of containers      that are placed on the    No longer
 67/548/EEC                      in the EU, used until 2017       market in the European    used
                                                                  Union
                                 Workplace hazard warnings
                                                                  Workplace Hazards in      No longer
 WHMIS 1988                      used in Canada, last used in
                                                                  Canada                    used
                                 2018 in favor of the GHS
Examples of common symbols
[edit]
                                             ISO        ANSI Z535 (United States)
 Warning                                                [a]
                                             7010
 General warning sign                                   —
 Flammable material
 Explosive materials
 Toxic material
 Corrosive substance
 Electricity hazard
 Radioactive material or ionizing
 radiation
 Biological hazard
 Floor-level obstacle
 Drop or fall hazard
 Slippery surface
Tape with yellow and black diagonal stripes is commonly used as a generic hazard warning. This can
be in the form of barricade tape, or as a self-adhesive tape for marking floor areas and the like. In
some regions (for instance the UK)[1] yellow tape is buried a certain distance above buried electrical
cables to warn future groundworkers of the hazard.