prEN ISO 22324

Security and resilience - Emergency management - Guidelines for colour-coded alert (ISO 22324:2022) prEN ISO 22324

Scope

This International Standard establishes the colour codes for expressing the degree of safety or
danger. The colour codes should be used to gain the attention of both first response personnel
and/or the people at risk about the severity of situation to solicit them to seek more information
or to take appropriate safety actions specified by prior notification. Unlike safety signs which
convey static information, colour codes should be used to let the people at risk know the recent
changes in status in terms of safety­danger continuum . The colours between red and green in
terms of hue will be used to express the status in terms of safety­danger continuum. The degree
of safetydanger continuum should be less than nine because of human capacity to distinguish at
one time.
This standard is applicable to all locations and all sectors where safety­related questions may be
posed.
However, it is not applicable to, generally speaking, to those sectors subject to a regulation
which may differ.