---
title: "Mechanical Engineering Expert Witness Opinions on Slipperiness of Shower Floor Admitted"
meta:
  "og:description": "Mechanical Engineering Expert Witness found qualified to competently testify as to the allegedly dangerous condition"
  "og:title": "Mechanical Engineering Expert Witness Opinions on Slipperiness of Shower Floor Admitted"
  author: "Expert Witness Profiler"
  description: "Mechanical Engineering Expert Witness found qualified to competently testify as to the allegedly dangerous condition"
---

# Mechanical Engineering Expert Witness Opinions on Slipperiness of Shower Floor Admitted

Posted on January 30, 2024 by Expert Witness Profiler

The case involved the Plaintiff, Anthony Cladd who fell and suffered injuries while using a shower stall at a truck stop owned by the Defendant, TA Operating, LLC. The Plaintiff asserted that the fall and injuries were a result of the shower stall being unsafe, and claimed that the Defendant breached a duty of care owed to him. The Plaintiff pursued legal action against the Defendant, alleging premises liability.

The Plaintiff claimed that the reason for his fall was the presence of standing water in the shower during use, stating that “The shower has a lot of standing water and was draining very slowly.” The Plaintiff alleged negligence on the part of the Defendant, asserting that they failed to maintain the shower drain, leading to a significant backup and slip hazard. Additionally, the Plaintiff accused the Defendant of failing to provide an anti-slip surface in the shower, neglecting to inspect the shower for unreasonably dangerous conditions, and not warning the Plaintiff about such conditions. The Plaintiff further claimed that the Defendant failed to correct the hazardous conditions, lacked adequate staff to inspect the shower, insufficiently trained their staff for identifying dangerous conditions, and did not adhere to its own corporate policies or have sufficient policies in place.

On June 6, 2022, the Court issued its Case Management and Scheduling Order, which set a deadline for the Plaintiff to disclose any retained experts and their reports by February 6, 2023. However, on February 17, 2023, the Plaintiff, having failed to comply with the deadline, filed a Motion for Extension of Time to disclose their experts. Subsequently, on February 24, 2023, the Court granted the Plaintiff’s motion, extending the expert disclosure deadlines by 45 days, with the new deadline set for April 10, 2023. On the specified date, April 10, 2023, the Plaintiff disclosed two retained expert witnesses, namely David Collette and Georges El-Bahri. The Plaintiff’s expert disclosures indicated that a copy of El-Bahri’s written report was being prepared and would be provided upon receipt. However, even three months after the initially expected date for producing El-Bahri’s report, the Plaintiff had not supplied any expert report for El-Bahri. The Defendant’s counsel made efforts to obtain the report by sending correspondences to the Plaintiff’s counsel. Despite these requests, no expert report was provided and the discovery was ultimately closed.

The Defendant filed a _Daubert_ Motion to Preclude the testimony and opinions of Plaintiff’s Expert, David Collette, a Motion to Strike Plaintiff’s Expert Witness Georges El-Bahri as he failed to furnish an expert report within the stipulated timeframe, and a Motion for summary judgment.

Collette admitted during deposition that he was not qualified to provide expert opinions on the coefficient of friction of the shower floor with standing water, and he did not conduct any testing under such conditions. The Defendant argued that Collette’s opinions were speculative, with questionable relevance to the trial issues. The methodology employed by Collette was deemed unscientific and unreliable, and the Defendant contended that his testimony would not assist the jury but instead lead to confusion.

## **Mechanical Engineering Expert Witness**

[David Collette](https://expertwitnessprofiler.com/expert-witness/David-Collette/1554635) holds a Bachelor of Science in Mechanical Engineering from the University of Manitoba, Canada and further pursued his education by earning a Masters of Business Administration from the University of Chicago. With an academic background in both engineering and business, Collette possesses over 18 years of extensive experience. Throughout his career, he has demonstrated expertise in developing, commercializing, analyzing, and troubleshooting walkway solutions, encompassing various aspects such as chemistry, tools, mats (walk-off, bath), cleaning processes, coatings, treatments, and flooring material selection. Currently serving as the President of Substratum Group, Collette leads the development of proprietary products and services aimed at supporting Walkway Management programs. His role involves providing customers with comprehensive solutions related to the selection, testing, care, and maintenance of walkways (e.g., floors, sidewalks, ramps, stairways) and bathing surfaces (e.g., tubs, showers).

## **Orthopedic Surgery Expert Witness**

[Dr. Georges F. El-Bahri](https://expertwitnessprofiler.com/expert-witness/Georges-El-Bahri/1543337), a Doctor of Osteopathic Medicine, earned his degree from Nova Southeastern University College of Osteopathic Medicine. He holds a Bachelor of Science in Biomedical Science from the University of South Florida. El-Bahri pursued postgraduate education and training, completing an Orthopedic Sports Medicine Fellowship at Andrews Research and Education Foundation, and an Orthopedic Surgery Residency at Largo Medical Center. His expertise extends to sports medicine injuries, particularly those of the knee and shoulder, with a focus on arthroscopic procedures, total joint replacements, and general orthopedic care. El-Bahri holds various positions, including Certified Life Care Planner at Life Care Plan MD, Extremity Surgeon at Interventional Pain Specialists, Extremity Surgeon at Spine Centers of America, Orthopedic Surgeon at Ortho One Jacksonville, and Orthopedic Specialist at Concentra-Occupational Health. He also maintains his private practice at Bahri Orthopedics and Sports Medicine Clinic.

## **Discussion by the Court**

The Defendant requested the Court to exclude David Collette’s entire testimony, contending that he lacked qualification, utilized invalid methodology, and his testimony would not assist the trier of fact. The Court observed that an expert’s qualification is determined by factors such as knowledge, skill, experience, training, or education, according to Federal Rule of Evidence 702. An expert is not automatically deemed unqualified if their experience doesn’t perfectly align with the matter at hand. The qualification assessment should consider the expert’s credentials in relation to the subject matter of the proposed testimony. If an expert is minimally qualified, objections to their expertise should be treated as matters of credibility and weight, rather than admissibility.

Collette holds a Bachelor of Science degree in Mechanical Engineering and served as a voting member on the technical committee for American National Standards Institute (ANSI)/National Floor Safety Institute(NFSI) B101.4 Test Method for Measuring the Wet Barefoot Condition of Surfaces, focusing on developing a barefoot standard for various surfaces such as bathtubs, shower enclosures, pool decks, and walkways in 2019. With over 14 years of experience in developing, launching, and auditing walkway and bathing surface safety programs. Collette does not possess a PhD in engineering. However, a preponderance of evidence indicated his qualification to testify on the coefficient of friction of the shower stall floor, its slipperiness, and relevant industry standards.

In the case of [Rosenfeld v. Oceania Cruises, Inc., 654 F.3d 1190, 1193 (11th Cir. 2011)](https://casetext.com/case/rosenfeld-v-oceania-cruises-inc-2), it was established that a qualified expert utilizing reliable testing methodology has the authority to testify about the safety of a Defendant’s flooring choice, determined by the surface’s coefficient of friction. Typically, coefficient of friction evidence is presented by an expert witness who also addresses industry standards and assesses whether the surface complies with them. Furthermore, according to [Sorrels v. NCL (Bahamas) Ltd., 796 F.3d 1275, 1285 (11th Cir. 2015)](https://casetext.com/case/sorrels-v-ncl-bahamas-ltd-4), a delay in testing the area where an accident occurred does not undermine the reliability of coefficient testing if the site has not materially changed since the incident. The case emphasized that weaknesses in the factual basis of an expert’s opinion are subject to challenges in terms of credibility and weight through cross-examination and the presentation of contrary evidence.

Collette conducted coefficient of friction tests using an American Slip Meter 925 tribometer and the ANSI A326.3 standard test method for measuring dynamic coefficient of friction (DCOF) of hard surface flooring materials. He asserted that the test method employed was the standard test used by manufacturers, interior designers, and architects for testing bathing surface floors. Collette performed the coefficient of friction test on the shower stall floor under somewhat different conditions than were present during the accident: it was over two years later, and there was no significant standing water present for his test. Additionally, he tested three samples of the shower stall floor instead of the entire surface. The Defendant could raise these considerations, but they pertain to the weight and credibility of the evidence, not its admissibility. Collette utilized an established methodology, the ANSI A326.3 standard test method, to assess the coefficient of friction of the surface. A preponderance of the evidence suggested that his testimony was grounded in a reliable methodology.

In _Sorrels_, it was established that expert testimony concerning the coefficient of friction (COF) of a flooring surface could be beneficial to a jury in a slip and fall case. The Court emphasized that challenging such evidence should be done through vigorous cross-examination, presentation of contrary evidence, and careful instruction on the burden of truth, as outlined in the _Daubert_ case.

Collette’s testimony closely parallels the testimony presented in _Sorrels_, proving beneficial to the jury in the slip and fall context. The preponderance of the evidence suggested that Collette’s testimony would aid the trier of fact by applying his expertise and remained relevant to the case. The _Daubert_ standard was deemed satisfied for all three prongs, and as a result, Collette’s testimony was not barred.

To establish a premises liability claim, the Plaintiff must demonstrate the elements of a negligence claim and prove that the Defendant had possession or control of the premises and notice of the hazardous condition. This includes showing: (1) the Defendant owed a duty, (2) there was a breach of that duty, (3) a causal link between the breach and the Plaintiff’s injury, (4) the Plaintiff suffered damages due to that injury, (5) the Defendant had possession or control of the premises, and (6) the Defendant had actual or constructive notice of the dangerous conditions leading to the injury.

The Defendant argued, as a matter of law, that a wet shower stall floor is not inherently dangerous and cannot impose liability on the owner. Premises owners are typically not liable for obvious risks unless an uncommon design or construction creates a hidden danger. In such cases, where a prudent invitee would not anticipate the danger, the premises owner may be found liable, as established in [Echevarria v. Lennar Homes, LLC, 306 So. 3d 327, 330 (Fla. 3d Dist. Ct. App. 2020)](https://casetext.com/case/echevarria-v-lennar-homes-llc). Additionally, a breach of industry standards serves as evidence of negligence, as outlined in [Hilliard v. Speedway Superamerica LLC, 766 So. 2d 1153, 1155 (Fla. 4th Dist. Ct. App. 2000)](https://casetext.com/case/hilliard-v-speedway-superamerica).

Considering the evidence favorably for the non-moving party, a material fact dispute exists regarding whether the shower stall floor posed a hidden danger. Collette, the Plaintiff’s expert witness, asserted in his written report that the wet dynamic coefficient of friction for the shower stall floor fell below industry standards for public showers and floors meant to be walked upon when wet. This condition, akin to the level-changing steps in _Echevarria_ and _Hilliard_, could be perceived as more slippery than reasonably expected, potentially adding a hidden danger. A jury could reasonably find that such conditions create liability for premises owners, as invitees may not anticipate these dangers.

The Defendant argued that Collette’s opinions were irrelevant and unsupported. However, in considering the evidence favorably for the non-moving party, Collette’s report and opinions were deemed relevant as they made it more likely that the shower stall floor had hidden danger, being more slippery than reasonably expected. Consequently, the Court determined that summary judgment was not appropriate for this matter.

According to Federal Rule of Civil Procedure 26(a)(2)(B), expert witness disclosures must be accompanied by a signed report if the expert is “retained or specially employed” for testimony. These disclosures must adhere to Court-ordered deadlines, as outlined in Federal Rule of Civil Procedure 26(a)(2)(D). Failure to make such disclosures could result in the expert being barred from presenting evidence at trial, unless the failure is deemed “substantially justified or harmless,” pursuant to Federal Rule of Civil Procedure 37(c)(1).

In this case, the Case Management and Scheduling Order stipulated a deadline for the Plaintiff’s disclosure of expert reports as February 6, 2023 . The Defendant emphasized that the Plaintiff did not disclose a report from Georges El-Bahri by that date. The Plaintiff failed to provide good cause for the untimely disclosure and did not respond to the Defendant’s Motion to Strike. The Court decided that Defendant’s Motion to Strike may be treated as unopposed. Consequently, it was deemed appropriate to strike El-Bahri as an expert witness for the Plaintiff.

## **Held**

The Court also denied the Defendant’s _Daubert_ Motion seeking to preclude the testimony and opinions of Plaintiff’s Expert, David Collette. Furthermore, the Court granted the Defendant’s Motion to Strike Plaintiff’s Expert Witness, Georges El-Bahri. The Court also denied the Defendant’s Motion for Summary Judgment.

The Court issued a ruling on January 08, 2024 to terminate all pending motions and administratively close the case pending further order of the Court. The parties were directed to file a joint stipulated form of final order or judgment or move the Court upon good cause to reopen the case on or before March 04, 2024.

## **Key Takeaways**

The Plaintiff, who suffered injuries in a truck stop shower stall, relied on the expert opinions of David Collette to establish the hazardous conditions of the shower floor. The Defendant contested the admissibility of Collette’s testimony, asserting that he lacked qualifications and used unreliable methodology. The Court, however, found that Collette, with his engineering background and extensive experience, met the qualifications for offering expert opinions on the coefficient of friction of the shower floor. The Court emphasized that objections to an expert’s expertise should be matters of credibility and weight, rather than admissibility. Collette’s use of established testing methodology and his relevance to industry standards strengthened the admissibility of his testimony. The Court also highlighted the significance of expert testimony in premises liability cases, acknowledging its potential to assist the jury in understanding complex issues such as the slipperiness of flooring surfaces. The Plaintiff’s expert Georges El-Bahri faced challenges to the timeliness of expert disclosures because the Plaintiff failed to provide good cause for the untimely disclosure and did not respond to the Defendant’s Motion to Strike, therefore barring the expert. Here, the Court underscored the importance of adhering to procedural rules for expert witness disclosures and the potential consequences, such as being barred from presenting evidence at trial.

## **Case Details**

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