What Is the Pendulum Test and How Does It Work?

The pendulum test is the recognised method for measuring a floor’s slip resistance, using a
swinging arm fitted with a rubber slider that mimics a heel strike. As the pendulum swings
across the floor, it records how much friction the surface produces, expressed as a Pendulum
Test Value (PTV). The higher the PTV, the more grip the floor has, and the lower the risk of a
slip.

The short why
The test exists because slip risk cannot be judged by eye. A floor can look clean, dry and
perfectly safe, and still produce a dangerously low PTV once it’s tested wet, worn, or under
real footfall conditions. The pendulum test replaces guesswork with a measurable, repeatable
number.

How the test actually works
The pendulum swings a spring-loaded rubber foot across a set length of floor surface, at a
fixed speed and angle, calibrated to simulate a person’s heel striking the ground mid-step. As
the foot contacts the floor, the friction between the rubber and the surface slows the
pendulum’s swing. A dial or digital reader captures how much energy was lost to friction, and
converts that into a PTV score.
Testing is typically carried out both dry and wet, since most floors behave very differently
under each condition. A surface with excellent dry grip can drop sharply once water, grease or
condensation are introduced, which is exactly the scenario that matters most in bars, kitchens,
poolside areas and entrances during wet weather.

What counts as a safe PTV score
Slip Safety Services works to HSE-recognised thresholds, where a PTV of 36 or above is
generally considered low risk, and anything below that indicates increasing risk as the
number drops. The value itself is only useful when it’s tied to the specific conditions it was
tested under: which zone, which footwear assumption, wet or dry.
This is where a single test can mislead if it’s treated as a permanent answer. A
reading of PTV 40 taken at installation says nothing about what that same floor measures two
years later, once cleaning products, wear and footfall have taken their toll.

Why one test isn’t the same as ongoing proof
This is the belief worth challenging directly. Many venues test once, get a passing score, and
treat that as compliance sorted. But a PTV reading is a snapshot, not a guarantee. Floors
change. The right response isn’t to test and file the result. It’s to measure, improve where the
number is weak, and keep proving the result over time.

The factors that shift a PTV score sit across a few clear areas:

• Contamination: grease, water, food debris or cleaning residue sitting on the surface
• Maintenance: the cleaning products and methods used, which can restore or damage
  grip depending on how they’re applied
• Surface wear: gradual degradation of the floor material itself under repeated footfall
• Environment: transitions between wet and dry zones, or areas exposed to weather
  ingress

Any one of these can move a floor from a safe PTV to a risky one, without the floor looking
any different to the eye.

Why this matters commercially, not just technically
For a hospitality or leisure operator, the PTV isn’t an abstract number. It’s the evidence base
for every decision that follows: whether a floor needs treatment, whether a cleaning regime is
actually working, and whether you have a defensible record if an incident ever happens. Slip
Safety Services has found that where measurement leads to genuine improvement, sites see a
57%+ average reduction in slip incidents. The number only delivers that value when it’s acted
on, not just filed.

What to do about it
Start by identifying your highest-risk zones, typically entrances, bars, kitchens and poolside
areas, and check when they were last tested. If you don’t have a dated PTV reading for each
of these, or the last one is more than a year or two old, that’s a gap worth closing before it becomes an incident.

Next step
If you’re not sure where your venue’s floors currently stand, the Slip Risk Scorecard is a quick
way to see where the gaps likely are, before committing to a full assessment.

Related questions
What is a good PTV score for a hospitality venue?
How often should floors be pendulum tested?
What’s the difference between a slip test and a full slip risk assessment?
Can cleaning products lower a floor’s PTV score?

You should Check these out;
“Check your venue with the Slip Risk Scorecard”
“The full method behind measure, improve, prove“