Pipemarkers Explained: Colour Coding for Pipes and Pressure Vessels

Quick facts

• Colour: Standardised base colours per content type (e.g. green for water, red for fire services, orange for electric power)
• Format: Coloured bands or full-length markers with text/arrows showing contents and flow direction
• Standard: AS 1345-1995 — Identification of the Contents of Pipes, Conduits and Ducts
• Where you’ll see them: Mining sites, food and beverage plants, water treatment facilities, power stations, hospitals

Why Pipe Colour Coding Exists

Unmarked or mislabelled pipes are a genuine safety hazard. A maintenance worker who assumes a pipe carries water when it actually carries a flammable liquid, compressed gas, or acid is one mistake away from a serious incident.

AS 1345 exists to remove that guesswork by giving every pipe a standardised colour and label, so anyone on site — including contractors who’ve never worked there before — can identify contents at a glance.

The Core Colour Groups

Under AS 1345, base identification colours are broadly grouped as:

• Water: Green
• Steam: Silver-grey
• Oils and flammable/combustible liquids: Brown
• Gases (gaseous, liquefied, vapours): Yellow-ochre
• Acids and alkalis: Violet
• Air: Light blue
• Fire-fighting materials: Safety red
• Electric power: Orange
• Communications: White
• Other fluids (including drainage): Black

A supplementary dark-blue band is added for pipes carrying materials for human consumption, and additional hazard colours or symbols are used where a specific danger (toxicity, radiation, high pressure) needs extra emphasis.

Placement Requirements

It’s not enough to colour the pipe — markers need to be positioned where they’re actually useful.

AS 1345 guidance recommends markers at every junction, valve, and wall or bulkhead penetration, with spacing no greater than roughly 8 metres apart on indoor runs (extending further on long, uninterrupted external runs).

Skipping this step is a common compliance gap we see on retrofit or expanded sites.

Ordering the Right Markers

Pinnacle Signage supplies AS 1345-compliant pipemarkers sized and coded correctly for your specific contents and pipe diameter. Browse the Pipemarkers range, or get in touch if you need a custom run for a non-standard content type or pipe size.

• Fast Dispatch: Most orders dispatched within 48 hours.
• Free Shipping: On orders over $100 AU wide (exceptions apply).
• Local Pickup: Available from our East Wagga Wagga, NSW warehouse, Mon–Fri 8am–5pm.

This article is general information only. Confirm exact colour and placement requirements for your site against the current edition of AS 1345.