Adventures in Slip Resistance Testing

Slip resistance testing opinions are often prone to problems, as discussed in a prior post.  Last year an opposing party disclosed an expert to offer that opinion in a case.  It too had problems.

The expert used the wrong standard.

The plaintiff slipped and fell.  Two employee witnesses who heard the fall and came to her aid found nothing on the floor.  Plaintiff later claimed there was some type of liquid on the floor, but didn’t take a picture.  There was no video of the area.

Plaintiff’s expert relied on ANSI/NFSI B101.1-2009, entitled “Test Method for Measuring Wet SCOF of Common Hard-Surface Floor Materials.”  SCOF is an abbreviation for static coefficient of friction.  Static friction is the “resistance opposing the force required to start the movement of one surface on or over another.”[1]  In other words, it measures the slip resistance required to start moving.  B101.1-2009 does not measure the dynamic coefficient of friction (“DCOF”), which is the slip resistance encountered when already in motion, like this plaintiff was.  By its own terms, B101.1-2009 had no application to the case.  Instead, the expert should have applied ANSI/NFSI B101.3-2012, “Test Method for Measuring Wet DCOF of Common Hard-Surface Floor Materials.”

I also argued the expert erred by using B101.1-2009 to compare his dry testing findings to wet testing findings.  He wrote “[i]t is also important to note that the extreme difference noted between the dry and wet slip resistance values would further promote the likelihood of slips.”  B101.1-2009 does not allow this comparison.  It expressly states the test “is not recommended for dry-surface testing and does not proposed to be an accurate measurement method for determining dry-surface slip resistance.  Dry-surface test data should not be compared to wet-surface data.  No inferences should be implied or concluded regarding dry vs. wet SCOF test results or data.”[2]

The expert’s report also cited 2006 International Building Code § 1003.3.4, which states “[w]alking surfaces of the means of egress shall have a slip-resistant surface and be securely attached.”  The expert did not claim the floor was not securely attached.  He instead asserted it was not “slip-resistant.”  However, the IBC does not define “slip-resistant.”  The only definition of slip resistant the expert provided was based upon B101.1-2009, which did not apply to a person in motion like this plaintiff was.

Finally, the expert asserted a measurement of 0.5 is “the generally accepted industry safety standard” for slip resistance.  My prior post discussed that.  The expert cited ANSI/NFSI B101.1-2009 as supporting this statement, but it does not state 0.5 is an industry standard.  It instead contains a table:

Wet SCOF Value Available Traction Remediation
mu 0.60 or above High Traction — lower probability of slipping Monitor SCOF regularly and maintain cleanliness
mu less than 0.60 but at or above 0.40 Moderate Traction — increased probability of slipping Monitor SCOF regularly and maintain cleanliness. Consider traction-enhancing products and technologies.
mu less than 0.40 Minimal Available Traction — higher probability of slipping Seek professional intervention. Consider replacing flooring and/or coating with high-traction products.

The table establishes only a range of slip resistance, not a generally accepted industry standard.  Even so, it references SCOF, which is when a person is starting to move.  It does not reference DCOF, for when a person is already in motion like this plaintiff was.

An Ohio court excluded opinion testimony under highly similar fact circumstances.  The testing in Pesci v. William Miller & Assocs., LLC “revealed an average dry slip-resistance, on a scale of 0 to 1.0, of 0.845, and an average wet slip-resistance of 0.215” and the plaintiff’s expert claimed “it is generally accepted that a slip-resistance value of 0.5 is the minimum considered safe for pedestrian ambulation.”[3]  The Ohio court rejected the validity of this opinion.  Specifically, “the Ohio Building Code only requires that walking surfaces have a slip-resistant surface, while the ANSI requires that walkway surfaces ‘be slip resistant under expected environmental conditions and use.’”[4]  The expert’s testimony demonstrated that the floor satisfied both “the OBC and ANSI as it had slip resistance when wet and dry.”  Finally, the expert “failed to cite any materials or regulations that would require a value of 0.5 for wet slip resistance.”  I argued the same analysis applied in my case.

The opposition contained a “supplemental” report from the expert.  I thought it was relatively weak and actually proved my point.  The expert wrote “[n]o tribometer or slip meter is capable of measuring WET dynamic coefficient of friction.”  This concession meant to me that the expert was admitting there was no method to measure the floor’s slip resistance under conditions that the plaintiff alleged she actually experienced.  The expert’s measurements were instead based upon something else that is irrelevant to the case because it was not what the plaintiff experienced.

As to the argument about what 0.5 means, the opposition cited not a single authority.  Nada, zilch, zero.  The expert’s supplemental report still provided no authority other than himself for support.  I argued this was similar to Brant v. State, where a district court’s order excluding a proposed expert who offered no evidence other than her own opinion to establish the reliability of her opinions was affirmed.  “But with no evidence to establish a scientific or other recognized basis for challenging the interrogation techniques utilized in this case … we have only Dr. Krawczyn’s ipse dixit that the techniques possibly used may have influenced Brant’s confession. This is not enough to establish an abuse of discretion in excluding such testimony.”[5]  This is substantively similar to the United States Supreme Court’s holdings.  “[N]othing in either Daubert or the Federal Rules of Evidence requires a district court to admit opinion evidence that is connected to existing data only by the ipse dixit of the expert.”[6]  Based upon that, I argued, just like occurred in Pesci v. William Miller & Assocs., LLC, the expert  “failed to cite any materials or regulations that would require a value of 0.5 for wet slip resistance.”[7]

The expert’s opinion was irrelevant.

The other argument was the expert’s opinion was pointless.  The fundamental question for the duty and breach elements of a negligence cause of action in a slip and fall case is notice.  Notice can be demonstrated if the defendant created the hazard, had actual knowledge of it, or constructive knowledge.  The plaintiff in my case presented no evidence linking her expert’s opinions to a fact indicating notice.  Even if 1) there was a wet slip resistance standard 2) that this floor failed, 3) there was no evidence in the case indicating the defendant had notice of that fact before the fall.  Plaintiff’s opposition did not address this argument.

No rebuttal expert

One of plaintiff’s arguments against the motion was that I had not disclosed a rebuttal expert.  I hadn’t because one was not needed, but that was beside the point.  The party offering the expert has the duty to satisfy the elements required to qualify the expert and get the opinions admitted.  What evidence the opposing party may offer is irrelevant to meeting your burden of proof.

What happened?

The motion was denied.  If you are surprised by that then you haven’t litigated enough cases yet.  The judge never entered any detailed findings, so the logic was semi-unclear other than the motion was not going to be granted.  The result did not particularly surprise me; after enough time you should be able to predict which judges will grant which motions.  This motion was an uphill battle, no matter what merit I thought it had.

Oh well, win some, lose others.  The case resolved on favorable terms literally days before trial, so there was no appeal.

[1] B101.1-2009 at § 3.8.
[2] Id. at §1.4
[3] 2011-Ohio-6290, ¶ 25 (Ohio App.)
[4] Id. at ¶ 26.
[5] 130 Nev. Adv. Op. 97, 340 P.3d 576, 581 (2014).
[6] General Elec. Co. v. Joiner, 522 U.S. 136, 146 (1997).
[7] 2011-Ohio-6290, ¶ 25 (Ohio App.)