Expert witness slip testing — evidence that holds up.

When you need an expert witness slip test

Slip-and-fall personal injury claims now run into hundreds of millions of pounds annually in the UK. The technical question at the heart of most of these claims is the same: what was the slip resistance of the floor at, or close to, the time of the incident? Answering it requires a test methodology that is both technically sound and legally defensible.

For claimant solicitors

If your client has been injured in a slip incident, contemporaneous slip resistance evidence dramatically strengthens the case. We attend incident sites, perform pendulum testing to BS 7976-2, and produce reports under UKAS accreditation that anchor the technical foundation of the claim.

For defendant solicitors and insurers

A UKAS-accredited slip resistance report demonstrating compliance with HSE thresholds is among the strongest defences available to a defendant. Where the floor was genuinely safe, we will say so plainly. Where it was not, we will say that too — our duty to the court overrides any commercial relationship.

For HSE investigations and prohibition notices

Where the HSE has issued a notice, evidence of slip resistance testing and a credible remediation plan is often the practical route to lifting the notice. We work to the timescales these matters demand.

What makes a slip testing report court-defensible

The anatomy of a defensible expert report:

• UKAS ISO 17025 accreditation — independent verification of laboratory technical competence
• Documented instrument calibration with traceability to national reference standards
• Slider conditioning records — the rubber slider must be prepared correctly before each test
• Photographic record of every test location with scale reference
• Raw test data — every individual swing, not just the median
• Wet and dry conditions, with potable water of recorded temperature
• Independent technical review by a second competent person before report sign-off
• Authorised signatory — the report carries personal accountability
• Compliance with CPR Part 35 where the report is intended for use in court proceedings

An "expert report" missing any of the above is, in our experience, vulnerable to challenge — sometimes terminally so.

Our expert witness experience

The Surface Performance technical team has produced slip resistance evidence in matters ranging from individual public liability claims to multi-claimant litigation against large retail and hospitality estates. Our reports have been instructed by claimant firms, defendant firms, insurers, and on a single-joint-expert basis.

Our duty as an expert witness is to the court, not to the instructing party. Our role is to produce technically defensible evidence — and to be just as willing to say a floor was safe as to say it was not.

Process and timescales

Following instruction, a typical expert witness engagement runs:

1. Day 1–2: Brief reviewed, conflicts checked, fee proposal issued
2. Day 3–10: Site attendance and on-site pendulum and Rz testing
3. Week 2–3: Draft report prepared, technical review, signed report delivered
4. Ongoing: Availability for Part 35 questions, joint expert meetings, and trial attendance as required

For genuinely urgent post-incident matters, we can attend within 24–48 hours. Reports for litigation are produced under signed CPR Part 35 declarations.

Fees

Site testing for litigation purposes typically falls between £900 and £2,500 depending on site complexity and number of test points. Expert opinion work, Part 35 questions, joint expert meetings and trial attendance are charged at our published expert hourly rate. We do not work on contingency or conditional fee bases — we believe these arrangements are inconsistent with the duty to the court.