Accident Reconstruction Expert’s Testimony About the Lid Locking Mechanism Admitted

Posted on July 25, 2025 by Expert Witness Profiler

This is a product liability case involving a Breville BPR600XL pressure cooker (the “Pressure Cooker”). Plaintiff, Hannah Frazier, claimed that suffered permanent injuries to her abdomen when the Pressure Cooker exploded, spraying super-heated liquid and steam across her body.

The Plaintiff retained Jeffrey D. Hyatt of Specialized Testing & Forensic Laboratory to inspect and test the Pressure Cooker and provide an expert report (“Hyatt Report” or “Report”). Hyatt inspected and tested the Pressure Cooker using the UL (for “Underwriters Laboratory”) 136 “Standard for Pressure Cookers.” The Defendant, Breville USA, Inc., filed a motion to exclude Hyatt’s testimony under Rule 702 and Daubert.

Accident Reconstruction Expert Witness

Jeffrey D. Hyatt specializes in conducting mechanical component and system testing engineering, mechanical system failure analysis, identification of materials failure mechanisms and scientific accident reconstruction.

Want to know more about the challenges Jeffrey Hyatt has faced? Get the full details with our Challenge Study report

Discussion by the Court

Breville did not challenge Hyatt’s qualifications as an expert; instead, it challenged the reliability of his principles and methodology.

UL 136

Breville contended that Hyatt’s testimony must be excluded in its entirety because Hyatt failed to establish that UL 136 applies or should apply to electrical pressure cookers, as opposed to stovetop pressure cookers.

However, the Court held that Hyatt’s testimony is sufficient to create, at a minimum, a question of fact as to whether it is appropriate to apply UL 136 standards to electric pressure cookers.

The Prescribed Testing Methodology

Breville next argued that, even assuming UL 136 applies, Hyatt did not utilize the prescribed testing methodology set out in UL 136. Hyatt, however, acknowledged as much during his deposition and explained why he intentionally chose not to follow precisely some of the procedures recommended in UL 136. It is clear that this was no oversight on his part.

Torque vs. Pounds Force

Breville contended that, “even using the wrong standard and applying that standard’s principles and methodology incorrectly, Hyatt demonstrated that the Pressure Cooker required more force to open than can be exerted by an average male or female.” According to Breville’s expert, the 26.3 pounds of force measured by Hyatt is equivalent to 131.5 “inch-pounds of torque, which is well in excess of what an average [person] has been observed to exert.” However, UL 136 prescribed the method for testing the force necessary to open a pressurized lid, and it speaks in terms of pounds of force, not torque.

The Measurement of the Locking Pin

Breville took issue with Hyatt’s purported failure to measure the lid locking pin while it was under pressure. Breville also contended that “Hyatt does not provide any support for his claim that Breville intended to use all .291 [inches] of the lid locking pin while under pressure” or “include any facts or data to support his conclusion that the Pressure Cooker was designed to use the entire .291 [inches] of the lid locking pin.”

Hyatt, however, explained that he made that assumption because he was not in possession of actual design documents from Breville to show what its intended design was, and he reserved the right to change his opinion if documents produced by Breville showed that, in fact, the manufacturer intended for the compressed pin to extend only .168 inches. In that event, Hyatt would modify his opinion to state that the compressed length of the locking pin was a design defect rather than a manufacturing defect that affected only the plaintiff’s Pressure Cooker.

Hyatt’s opinion, in any event, is that the length of the pin in the case of this particular pot was insufficient to prevent it from opening under pressure. The Court held that Breville’s objections did not make his opinion unreliable or inadmissible.

The Reliability of the Data in Figure 13

Breville pointed out an error on a data chart in Hyatt’s Report purporting to show that the internal pressure of the Pressure Cooker was negative for the majority of the test. It asserted that Hyatt “fails to account for any condition that would make the internal pressure of the cooker less than zero for the majority of the test,” thus making the “data he offers in the chart . . . unreliable and insufficient.” As set forth above, Hyatt did explain this discrepancy in his deposition and accounted for it. It appeared that the only difference this error would have made would be to shift the maximum internal pressure of the Pressure Cooker by .5 psig, but it did not appear to have had any effect on Hyatt’s other calculations.

Although this error might detract from Hyatt’s credibility before the jury, the Court held that it does not render his opinions unreliable or inadmissible.

Breville’s Intentions

Finally, Breville took issue with Hyatt’s finding that Breville intended for the Pressure Cooker to “meet the automatic locking requirements of UL 136” on the basis that this finding is not supported by sufficient evidence, given that the Pressure Cooker itself states that it was intended to comply with US 1026 and UL 1083.

Hyatt made it clear in his deposition that UL 136 is the locking mechanism standard and that the “industry requires” any pressure cooker lid to remain locked while the contents are under sufficient pressure that liquid could be ejected if it were opened.

The fact that the Pressure Cooker here has a locking mechanism that engaged below 0.25 psig of pressure indicated to him that Breville intended to comply with industry safety standards, irrespective of whether it identified UL 136 on the Pressure Cooker’s label. In other words, according to Hyatt, the design of Breville’s locking mechanism itself demonstrated Breville’s intent that its pressure cookers be safe and in compliance with industry standard.

Whether Hyatt’s Testimony Will Assist the Jury

Breville asserted that, for all of the reasons addressed above, Hyatt’s testimony would not assist the jury in understanding the evidence or determining a fact at issue in this case. The Court finds, as set forth above, that Breville’s arguments are more properly directed to the weight to be accorded Hyatt’s testimony by the jury rather than to its admissibility.

Breville contended that Hyatt’s hypothesis—that the lid opened without resistance—contradicted his finding that it took 26.3 pounds of force to open while under pressure and that Hyatt “fails to explain how his conclusion that the Pressure Cooker required 26.3 pounds of force to open while under pressure has any bearing on whether a defect caused Plaintiff to be able to open the Pressure Cooker lid ‘easily’ and ‘with no resistance’ as she has testified to.

But Hyatt addressed this purported inconsistency in his deposition as well. He testified that consumers whose pressure cookers he has tested frequently describe the lid as opening “with “no resistance” or as being “easy to open,” and he did not understand Frazier to mean literally that the lid had no resistance when she opened it.

Held

The Court denied Breville’s motion to exclude the testimony of Jeffrey D. Hyatt.

Key Takeaway:

Hyatt’s opinions are based on sufficient facts and data, are the product of reliable principles and methods, and reflect a reliable application of the principles and methods to the facts of this case.

The Court denied Breville’s motion, insofar as it sought the exclusion of Hyatt’s testimony.

Case Details:

Case Caption:Frazier V. Breville USA, Inc.
Docket Number:3:23cv563
Court Name:United States District Court, Tennessee Middle
Order Date:July 24, 2025