Prior to 1st Jan 1997, the code of practice for fire extinguishers in the UK was BS 5423, which advised the colour coding of fire extinguishers as follows:
Water – Red
Foam – Cream
Dry Powder – Blue
Carbon Dioxide (CO2) – Black
Halon – Green (now ‘illegal’ except for a few exceptions such as the Police, Armed Services and Aircraft).
New extinguishers should conform to BS EN 3, which requires that the entire body of the extinguisher be coloured red. A zone of colour of up to 5% of the external area can be used to identify the contents using the old colour coding shown above.