EN 1177 provides two
methods. We carry out both — on site and in the laboratory — using an instrumented headform that
records the deceleration of each controlled drop.
METHOD 1
Determination of critical fall height
The core test. An instrumented headform is dropped onto the surface from increasing heights
until the HIC or gmax limit is reached. The result is the surface's certified critical
fall height — used for specification, procurement and product certification. Carried out in the
laboratory on samples, or on site on the installed surface.
METHOD 2
On-site impact attenuation
Introduced in the 2018 edition for confirming, after installation or later in a surface's
life, that it still attenuates impact as required for that location. Ideal for handover sign-off
and for periodic checks within an inspection regime.
The instrumented headform records deceleration on each controlled drop.
What to expect
A straightforward four-step process.
1. Scope. Tell us the equipment heights, surface type and location. We confirm whether on-site or laboratory testing fits.
2. Test. We carry out the drop tests across the impact area, recording HIC and gmax at each point.
3. Report. You receive a clear report stating the critical fall height with measurement uncertainty, and a pass/fail against the equipment above.
4. Advice. If a surface falls short, we set out the options objectively — we have nothing to sell you in the way of surfacing.
Independent by design. We are a testing laboratory, not a surfacing manufacturer
or installer. Our results are issued under our UKAS accreditation (Lab No. 7933) with no
commercial interest in the outcome.
Request testing
Ready to book a test?
A short description of the site is all we need to scope the work and quote.