text: A widely used British Standard (BS) for marking equipment is:
  * BS 1710:2019 Graphical symbols — Safety colours and safety signs — Registered safety signs
  The Standard stipulates the colours to be used. These are as follows:
  In addition to the basic colours, certain safety colours are used:
  The arrangement of markings is for the safety colour to be between bands of the basic colour.
  Firewater service would be:
  The pipe contents must be identified adjacent to the banding. This can be done by giving either:
  * The full name
  * Abbreviation
  * Chemical symbol
  * Refrigerant number
  * Coloured bands (user specified)
  The direction of flow should also be identified near the banding.
  Examples using this system are as shown.