Industrial pipe marking: BS 1710 explained

BS 1710 is the UK standard for identifying the contents of pipelines by colour. It's used across industrial sites, water utilities, hospitals (medical gas), and chemical processing.

The basic colour-coding

BS 1710 uses ground colours (the main colour painted on the pipe) and code colours (banded sections to identify specific contents):

• Green — water (with code colour bands for type: drinking water, hot water, cooling, fire main)
• Silver-grey — steam
• Brown — oils (mineral, vegetable, fuel)
• Yellow ochre — gases (with code colour bands for type: medical, industrial, fuel)
• Violet — acids and alkalis
• Black — drainage and waste
• Light blue — air
• Aluminium-grey — refrigerant

Code colour bands further specify content. For example, a green pipe with a red band indicates fire main; with a blue band, drinking water.

Where to mark pipes

• At every point of entry and exit through walls and floors
• Adjacent to every valve, joint, and inspection point
• On long straight runs at intervals not exceeding 6m (visible from any working position)
• Adjacent to safety-critical equipment (emergency shutoffs, fire main hydrants)
• At branches and tees

Direction of flow

BS 1710 also requires arrows showing direction of flow at each marking. For circulating systems, both directions are shown. Critical for maintenance work — turning a valve the wrong way on a high-pressure line is a major incident category.

Hazardous content additions

Where contents are hazardous, additional warning labels apply alongside the BS 1710 marking. Toxic substances may add a CLP/GHS pictogram. High-pressure systems may add pressure-rating labels. Asbestos-containing lagging requires additional asbestos warning.

Materials

Self-adhesive vinyl with chemical-resistant lamination is the workhorse for indoor pipe identification. For outdoor pipework or wash-down environments, pre-formed clip-on pipe markers provide better long-term durability. For high-temperature pipework (steam, hot water), high-temperature self-adhesive vinyl rated to 150°C+ is needed.

Direct Signs supplies BS 1710 pipe identification labels, banding, and clip-on markers in stock and bespoke. We supply major UK water companies, hospitals, and industrial sites — see our water treatment works signage page for sector context.