Why does slip risk increase in winter?
Slip risk increases in winter because pedestrian surfaces are more likely to stay wet, collect contamination and dry slowly. Rain, tracked-in water, condensation, cleaning residue, leaves and surface wear can reduce available friction. Existing pedestrian surfaces exposed to wet conditions should be assessed under AS 4663:2013.
Slip risk is the likelihood that a pedestrian surface, footwear, contamination and use conditions combine in a way that increases the chance of slipping.
Why winter changes surface performance
Winter does not make every surface unsafe. It exposes surfaces that are already vulnerable.
During warmer months, a floor, ramp or walkway may dry quickly after rain or cleaning. In winter, the same surface can remain damp for longer. Lower temperatures, reduced evaporation, shaded areas and repeated wet-weather exposure all affect how a surface performs underfoot.
The issue is not just water. Winter moisture mixes with contaminants that are already present on the surface: dirt, leaves, tyre residue, cleaning chemicals, grease, dust and general pedestrian traffic residue. That mixture can form a thin layer between footwear and the walking surface, reducing available friction.
A surface that feels safe when dry may perform differently when wet.
Where winter slip risk is most common
Winter slip risk is usually highest where water is expected, tracked in or slow to dry. Common locations include:
- building entrances
- external ramps
- tiled entries
- covered walkways
- car park pedestrian paths
- painted crossings and walk zones
- public footpaths
- outdoor stairs
- pool and aquatic centre entries
- shopping centre entries
- school and childcare pick-up areas
- hospital and aged care entries
These are often transition zones. People move from outside to inside, from rougher surfaces to smoother ones, or from dry areas to wet areas. Those transitions matter because the walking condition can change in one or two steps.
Why visual inspection is not enough
Winter slip risk is often underestimated because surfaces may still look clean, maintained and compliant. A polished tile, sealed concrete surface or painted walkway can appear safe while performing poorly in wet conditions.
Visual inspection can identify obvious hazards such as pooling water, algae, worn coatings or loose mats. It cannot confirm slip resistance. Microtexture, surface wear, contamination film and wet-weather performance need to be measured.
That is where slip resistance testing becomes useful. It gives facility managers, councils, builders and property teams a measurable result instead of a visual guess.
Which standard applies to winter slip risk?
For existing pedestrian surfaces, AS 4663:2013 applies. It provides test methods for measuring the slip resistance of existing pedestrian surfaces in wet and dry conditions.
For new pedestrian surface materials on installation, AS 4586:2013 applies. It classifies new materials under controlled test conditions before they are placed into pedestrian use.
A surface may have had an AS 4586:2013 classification on installation, but once it has been used, cleaned, worn or coated, its in-service performance should be assessed under AS 4663:2013.
Why entrances deserve special attention
Entrances are one of the most common winter risk points because they combine several factors at once. Water is brought in on footwear, umbrellas, clothing, trolleys, prams, mobility aids and delivery equipment. Entry mats may become saturated. Internal tiles may be smoother than external paving. Cleaning frequency may increase.
A dry internal floor may not be the problem. The problem may be the first few metres where wet shoes meet a smoother surface. This is why entry areas should be assessed as actual use zones, not simply as architectural finishes.
Why ramps and slopes matter
Sloped surfaces create additional demand on pedestrian traction. When a ramp or sloped walkway becomes wet, the available slip resistance becomes more important because people are walking against gravity, changing speed or adjusting balance.
AS 4663:2013 includes provisions relating to slope correction. For facility managers and councils, this means ramps should not be treated as ordinary flat surfaces when interpreting slip risk.
What should be tested before winter?
Testing priorities should be based on exposure and consequence. High-use surfaces that become wet, stay wet or have a history of complaints should be assessed first.
Useful test locations include:
- main entries
- external ramps
- public footpaths near buildings
- car park pedestrian zones
- painted crossings
- pool surrounds and change room entries
- loading and delivery interfaces
- areas recently coated, sealed or pressure washed
- surfaces where a slip, near miss or complaint has occurred
The goal is not to test every square metre. The goal is to identify representative risk points and confirm whether the surface performs appropriately under expected conditions.
Frequently Asked Questions
Does winter make floors more slippery?
Winter can make floors more slippery when surfaces become wet, contaminated or slow to dry. The increased risk comes from the interaction between moisture, surface texture, cleaning residue, wear and pedestrian use. Testing confirms whether the surface still provides suitable slip resistance.
Should floors be tested before winter?
Floors and pedestrian surfaces should be tested before or during winter if wet conditions are reasonably foreseeable, especially at entries, ramps, external paths, car parks and public interfaces. Testing helps identify problems before complaints, incidents or insurance questions arise.
Can a floor pass when dry but fail when wet?
Yes. A surface can perform adequately in dry conditions but become slippery when wet. Dry testing does not confirm wet-weather performance. Wet pendulum testing is used where water or wet contamination is likely to affect pedestrian safety.
Which standard applies to existing surfaces in winter?
AS 4663:2013 applies to existing pedestrian surfaces. It is used to measure slip resistance in wet and dry conditions after a surface has been installed and made available for pedestrian use.
written by:
Brendan Sheedy
Brendan Sheedy is the founder of Zerofal Slip Test Specialists. He leads Zerofal’s NATA-accredited slip resistance testing services and brings more than 20 years of experience in commercial facility management, flooring risk assessment and compliance testing.
Need to assess winter slip risk?
If a surface becomes wet, stays damp or receives complaints during winter, visual inspection is not enough.