Low temperature warning sign (W010)
A yellow triangle with a snowflake warns of low temperatures or freezing conditions. It is sign W010 in ISO 7010; in labs it marks cryogens such as liquid nitrogen.
Easily confused with
How to read it
ISO 7010 registers W010, “Low temperature/freezing conditions, warning”, among the warning signs that ISO 3864-1 says indicate “a specific source of potential harm”. Great Britain’s Safety Signs and Signals Regulations 1996 list the same sign as “Low temperature”. On lab doors it stands for cryogens: Kansas State University’s safety office defines cryogens as liquids with a normal boiling point below −150 °C (−240 °F) and names argon, helium, hydrogen, nitrogen and oxygen as the gases most often used in that state.
Also searched as: cryogenic symbol, cryogen symbol, freezing conditions sign, liquid nitrogen symbol, low temperature symbol, snowflake warning sign, W010.
These explain what each sign means and which standard sets it. What to do in a laboratory is set by the lab’s own rules, signs and trained staff; for a chemical, refer to its label and safety data sheet.
What a cryogen sign covers
The University of Houston’s lab door signs have a cryogen pictogram for substances stored cold enough to damage human tissue. Its safety office adds that the hazards include those of the chemical itself, such as asphyxiation when it displaces oxygen. Kansas State University’s lab signs carry a cryogen symbol of their own.
Look-alikes
The hot surface sign, W017, has three wavy lines rising from a surface in the same triangle.
Read next
- Next in Lab safety symbolsBiosafety level sign (BSL-1 to BSL-4)A sign with the biohazard symbol and a biosafety level, BSL-1 to BSL-4, tells you what level of containment a lab works at. BSL-1 is for agents not known to cause disease in healthy adults; BSL-4 is for dangerous agents with no vaccine or treatment.
- On a chemical label, refrigerated liquefied gases carry the GHS gas cylinder.Gas cylinder (GHS04)The GHS pictogram for gases under pressure: compressed, liquefied, refrigerated liquefied and dissolved gases.
More lab safety symbols
The same shape elsewhere
Browse symbols drawn with stars or triangles.
Sources
- ISO 3864-1:2011, Graphical symbols — Safety colours and safety signs — Part 1: Design principles for safety signs and safety markings (preview), ISO 3864-1:2011, International Organization for Standardization, preview via iTeh Standards, 3.16, Table 1
- ISO 7010:2011, Graphical symbols — Safety colours and safety signs — Registered safety signs (preview), ISO 7010:2011, International Organization for Standardization, preview via iTeh Standards, Table 1
- The Health and Safety (Safety Signs and Signals) Regulations 1996, Schedule 1, SI 1996/341, legislation.gov.uk (UK Government), Part II, 3.2
- Laboratory Doorsigns, University of Houston Environmental Health and Safety, Hazards
- K-State Laboratory Signs, Kansas State University Environmental Health and Safety, Cryogen Symbol
Researched, edited and approved by Rory Hansen before publishing. Last reviewed October 9, 2026. How we research
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