## Facts

- Mobil Chemical Co. owned a chemical plant under construction by an independent contractor, C.F. Braun.
- A plant unit was completed, tested, accepted by Mobil, and placed into “commissioning,” including running acetic acid through the system.
- The process included a high-pressure feed line to a leach section, protected by rupture discs and a relief valve intended to open at a set pressure.
- A first over-pressure event occurred; the relief system operated, Mobil replaced rupture discs, and commissioning continued.
- A second over-pressure event followed; the relief mechanism malfunctioned, and pressurized acetic acid escaped into the air as vapor.
- Plaintiffs Bell and Hurley, contractor employees working nearby, inhaled acetic acid vapor and suffered respiratory injuries.
- Mobil’s engineer testified the failure was attributable to defective or improperly manufactured/installed piping or fittings rather than Mobil’s operation.
- The jury found no specific negligent act by Mobil but found liability under res ipsa loquitur-type submissions; the trial court awarded each plaintiff $12,000.
- The intermediate appellate court reversed and remanded for a new trial, holding res ipsa was improperly submitted.
- Mobil sought further review; plaintiffs did not seek review to reinstate the trial judgment.

## Issues

1. Whether a res ipsa loquitur case must be submitted to the jury through special issues expressly tracking res ipsa elements, or may be submitted through general negligence and proximate-cause issues with appropriate instructions.
2. Whether evidence suggesting alternative causes (such as contractor manufacturing/installation defects) legally defeats the res ipsa inference of negligence.
3. Whether, when only the defendant seeks review, the court may alter a remand ordered by the intermediate appellate court in favor of non-petitioning plaintiffs.

## Decision

- The court disapproved the intermediate appellate court’s requirement that res ipsa cases be submitted using specialized, element-by-element res ipsa special issues.
- The court held that evidence of other possible causes did not, as a matter of law, refute the res ipsa inference; it created a fact dispute for the jury.
- The court nevertheless affirmed the judgment remanding the case for a new trial because plaintiffs did not seek review of the remand order.

## Legal Principles

- Res ipsa loquitur is an evidentiary rule permitting an inference of negligence from the occurrence and surrounding circumstances; it is not a separate cause of action.
- A res ipsa theory may be presented through ordinary negligence and proximate-cause submissions, accompanied by proper instructions, without mandatory separate “res ipsa” special issues.
- Evidence pointing to an alternative cause does not automatically bar res ipsa; it generally presents a jury question unless it conclusively negates the inference as a matter of law.
- When only one party petitions for review, the reviewing court may correct legal reasoning but may be constrained from granting affirmative relief to the non-petitioning party beyond the judgment under review.

## Conclusion

The court rejected a rigid, formulaic approach to submitting res ipsa loquitur to juries and held that competing explanations for an accident typically go to the jury, but it left the new-trial remand in place because the plaintiffs did not seek review to restore their trial judgment.


Mobil Chem. Co. v. Bell, 517 S.W.2d 245 (Tex. 1974)