Slip resistance on a polished floor is a measured property, not a texture impression. If you cannot show a number, you have no defence when someone falls and the floor is blamed.

What to measure

Test	Output	Typical target
Pendulum (BS 7976 / ASTM E303)	PTV, wet and dry	Wet PTV 36+ pedestrian, 45+ ramps
Tribometer (DIN 51130)	R rating	R10-R11 for commercial interiors
Surface profile (CSP)	CSP 1-3	CSP 2 typical polished

Where polished floors usually pass and fail

Dry polished concrete is rarely a problem. Wet polished concrete at high gloss fails more often than owners expect, particularly on ramps, entry transitions and areas with food or drink spills. Honed finishes (400-800 resin) generally test 5-15 PTV points higher than a mirror finish on the same slab.

Test procedure that survives scrutiny

1. Test in the finished condition, after the guard or densifier has cured, not on a sample panel alone.
2. Take at least three readings per zone and report the lowest, not the average.
3. Test wet where the zone can get wet in service; wetting with clean water, not surfactant.
4. Record slab temperature, slider rubber grade and calibration date.
5. Test again at handover after cleaning, because cleaning residue changes readings.

If the readings are short

• Mechanical: re-hone the last step coarser. The most durable fix, and it does not add a film.
• Chemical: an anti-slip treatment can add 5-10 PTV points but hazes the finish and needs reapplication.
• Design: add matting, change the finish in the wet zone, or add a drainage fall so water does not stand.

Documentation

Reading the numbers: PTV, DCOF and R-values

Three different numbers get quoted in slip conversations, and they are not interchangeable. Mixing them is how a floor that passes one test is reported as failing, or how a genuinely slippery floor is signed off.

Metric	What it describes	Typical threshold cited	Where it is used
PTV (pendulum test value)	Friction of a rubber slider on wet or dry surface	36+ wet for pedestrian areas, 40+ where slopes or steps exist	UK, Commonwealth and insurer-driven assessments
DCOF (dynamic coefficient of friction)	Friction measured by a tribometer on a wet tile	0.42 wet minimum	US tile specifications, often applied to polished concrete by analogy
R-value / class	Ramp test classification of a flooring product	R10 to R12 for level public areas	Product certification and specification clauses

The number that matters is whichever one the specification or the insurer names. If the contract says PTV 36 wet, a tribometer reading of 0.45 is not evidence either way; it is the wrong instrument producing a number nobody asked for. Ask which metric before testing, and test with a calibrated instrument whose certificate is in date.

Test points and conditions that decide the result

• Test wet, and test where water actually lands: entrance mats, drink stations, dishwasher returns, washroom doors and any slope.
• Take three readings per point and report the average and the lowest. A single high reading at the centre of a dry area proves nothing.
• Record surface temperature and water temperature. Cold water on a cold floor reads lower than the same floor tested warm.
• Clean the surface exactly as the maintenance specification says before testing. A floor tested with a grease film measures the grease, not the finish.
• Note the finish grit and any guard or anti-slip treatment in place, because all three shift the wet value and any of them can change later.

A polished floor usually passes dry by a wide margin and lands close to the threshold wet. That margin is the reason the test conditions must be written down: the same floor can read 45 wet after a fresh clean and 33 wet after a week of kitchen traffic.

Remedies, ranked by cost and disruption

• Deep clean and degrease. Cheapest first step, and often the whole fix. Restores 5-15 PTV points on a floor that was merely filmed.
• Finer finish on the wet zone only. A 1500-2000 finish in the traffic area raises wet friction without changing the look of the whole floor.
• Chemical anti-slip treatment. Applied after the final polish; effective, but re-application intervals must go into the maintenance spec or it wears off silently.
• Mechanical surface texturing. Last resort in an operating area: changes appearance, requires masking and produces dust that must be controlled.

Whatever the remedy, re-test after it and file the reading against the handover numbers. An untested remedy is an assumption, and slip claims are decided on records rather than on intentions.

Put the readings, method, zones and photos into the handover pack, and hand a copy to the facility manager. On commercial floors the number matters more than the gloss: a 40 PTV honed floor is a better commercial decision than a 25 PTV mirror floor that photographs well.