UNI EN 981 : 2009

Foreword
1 Scope
2 Normative references
3 Definitions
4 Ergonomic principles for the design and application
  of auditory and visual signals
  4.1 General
  4.2 Principles for distinctive characters
  4.3 Qualities of auditory signals
  4.4 Qualities of visual signals
5 System of auditory and visual signals
  5.1 Scheme of purposes and character
  5.2 Scheme of auditory signal character
  5.3 Scheme of visual signal colours
6 Testing
Annex ZA (informative) - Relationship between this
         European Standard and the Essential Requirements
         of EU Directive 98/37/EC, amended by 98/79/EC
Annex ZB (informative) - Relationship between this
         European Standard and the Essential Requirements
         of EU Directive 2006/42/EC

This European Standard is applicable to all danger and information signals which have to be clearly perceived and differentiated as specified in 5.3 of EN 292-2:1991, by other requirements or by the work situation, and to all degrees of urgency - from extreme urgency to an ALL CLEAR situation.