If a product is not unreasonably dangerous at the time it leaves the control of the manufacturer or seller but was made unreasonably dangerous by subsequent unforeseeable alteration, change, improper maintenance or abnormal use, the manufacturer or seller is not liable.
Product altered or abnormally used
Tenn. Code Ann. § 29-28-108, under Products Liability Actions.
Tenn. Code Ann. § 29-28-108