In Bennett v. Greeley Gas Co., 969 P.2d 754 (Colo. App. 1998), the plaintiffs were injured in a gas explosion, which was caused by a leak in a pipeline that had been damaged and negligently repaired during excavation work eighteen years earlier. To show that defendant did not meet its standard of care, the trial court allowed plaintiffs to introduce evidence of a federal safety regulation that had been enacted six years after the repair. On appeal, a division of this court remanded the case for a new trial, stating that: At least absent evidence that a safety code or regulation was intended to apply retroactively, it has generally been held that evidence concerning them is not admissible to establish the standard of care at a time before their enactment. Bennett v. Greeley Gas Co., supra, 969 P.2d at 759. In Bennett, a later regulation was used to establish an apparently higher standard of care than was applicable during defendant's earlier repair of a pipeline.