Can an employer be held liable if an employee is injured while operating a machine designed and manufactured by their own company?

[143 Cal.App.3d 38] In Shook, the employee was injured while operating a machine designed and manufactured by his employer for its own use in its own plant. "International created the machine exclusively for its own use in its own plant and premises. It did not sell the machine or in any way place it in the stream of commerce. Rather, it was but an occasional or casual manufacturer, and thus not subject to strict liability [citation]. Its design and construction of this machine was but auxiliary to its principal manufacturing operation. As such, it does not subject International to products liability to its employees [citation]." (Shook v. Jacuzzi, supra, 59 Cal.App.3d 978, 981, 129 Cal.Rptr. 496.)