The definition of corporate manslaughter is quite clear.
Following R v. Prentice, a breach of duty amounts to 'gross negligence' when there is indifference to an obvious risk of injury to health; actual foresight of the risk coupled with the determination nevertheless to run it; appreciation of the risk coupled with an intention to avoid it but also coupled with such a high degree of negligence in the attempted avoidance as the jury consider justifies conviction, and inattention or failure to advert to a serious risk which goes "beyond inadvertence" in respect of an obvious and important matter which the defendant's duty demanded he should address.