ISO W011 Slippery Surface Sign

What ISO 7010 W011 Warns About

W011 warns of a slippery surface. The pictogram shows a figure losing footing on a sloping line, drawn in black inside the ISO 3864-1 warning triangle on a yellow field. It tells people that the floor or walking surface ahead offers reduced traction and that they should adjust how they move — slow down, take shorter steps, and use handrails where available. Slips are among the most common causes of workplace injury, and the sign exists to prompt that change in behaviour before a person commits their weight to an unreliable surface.

The sign warns of the condition but does not name its cause. A floor can be slippery from spilled water, oil or grease, ice, process residue, loose material, or wet cleaning in progress, and W011 covers all of them without specifying which applies. Where the cause matters to the response — for example a chemical spill rather than plain water — supplementary text or a more specific sign is added. On its own the pictogram simply says the surface cannot be trusted for normal walking speed.

When and Why It Is Used

W011 is used both for routine conditions and for temporary ones. Some areas are predictably slippery — food-production floors subject to washdown, entrances that collect rainwater, cold rooms that form condensation or frost, and chemical-transfer zones — and warrant permanent signage. Others become slippery briefly, such as during and after cleaning, and are managed with portable A-frame signs that are put out while the hazard exists and removed once the floor is dry. The two uses call for different sign formats but the same warning message.

Signage is a control of last resort, not a substitute for fixing the problem. Preventing the slip — through drainage, anti-slip flooring, prompt spill clean-up, and appropriate footwear — protects people more reliably than a sign does, and safety management approaches generally place engineering and housekeeping controls above warnings. W011 is most defensible when it accompanies genuine efforts to reduce the hazard, and least defensible when a permanent slippery-floor sign is used to normalise a problem that should have been engineered out.

Placing the Slippery-Surface Sign

Position W011 so it is seen before a person reaches the slippery zone, giving them time to slow down and change their footing rather than discovering the problem underfoot. At building entrances that means placing it on the approach in wet weather; at a spill, it means bracketing the affected area rather than marking only its centre. On stairs and ramps, where a slip is more likely to cause serious injury, the warning should be positioned at the top of the descent where the reader still has control.

For temporary hazards, discipline about removal matters as much as placement. A wet-floor sign left standing long after the floor has dried teaches people to walk past it, so that the one occasion it marks a real hazard is also ignored. Portable signs should be deployed the moment cleaning or a spill creates the risk and collected as soon as the surface is safe. Where slippery conditions recur in the same place, pairing signage with anti-slip treatment or matting addresses the cause rather than relying on the warning alone.

Related Signs and Complementary Measures

W011 is often used alongside other warnings for the same route. Where a slippery floor is also a spillage of a hazardous substance, a chemical or corrosive warning may be added so responders treat the liquid correctly, not just the traction risk. Where the surface leads to a change in level or a step, a separate warning for that hazard is appropriate, since a slip near an edge or drop has more serious consequences than one on level ground.

The most effective complement to W011 is mandatory footwear signage where anti-slip shoes are required, and physical measures such as drainage channels, grated flooring, absorbent mats, and grit or anti-slip coatings on ramps and stairs. Investigations of slip incidents commonly consider the surface, footwear, contamination, and cleaning regime together, so the warning sign is best treated as one visible element of a broader slip-management approach rather than the whole answer to a persistently slippery area.

What does the slippery surface warning sign mean?

The figure slipping on a sloped line in a yellow triangle is ISO 7010 W011, warning that a walking or working surface offers reduced traction. Causes include water, oil, ice, process residue, or wet cleaning. The sign prompts people to slow down, take shorter steps, and use handrails before reaching the affected area.

When should I put out a wet-floor sign?

Deploy a portable W011 sign the moment a spill or cleaning creates a slip hazard, and position it so people see it before they reach the wet area. Remove it as soon as the surface is dry and safe. Leaving wet-floor signs standing after the hazard has gone trains people to ignore them, weakening the warning when it genuinely matters.

Is a slippery-floor sign enough to meet my safety duties?

Usually not on its own. Signage is a lower-tier control; preventing the slip through drainage, anti-slip flooring, prompt spill clean-up, and suitable footwear protects people more reliably. W011 is most defensible when it accompanies genuine efforts to reduce the hazard, rather than being used to normalise a floor that should be engineered to be safer.