Ohio Rev. Code Ann. § 2307.901 – Silicosis or mixed dust disease claim - multiple defendants - substantial factor test

(A) If a plaintiff in a tort action alleges any injury or loss to person resulting from exposure to silica or mixed dust as a result of the tortious act of one or more defendants, in order to maintain a cause of action against any of those defendants based on that injury or loss, the plaintiff must prove that the conduct of that particular defendant was a substantial factor in causing the injury or loss on which the cause of action is based.
(B) A plaintiff in a tort action who alleges any injury or loss to person resulting from exposure to silica or mixed dust has the burden of proving that the plaintiff was exposed to silica or mixed dust that was manufactured, supplied, installed, or used by the defendant in the action and that the plaintiff's exposure to the defendant's silica or mixed dust was a substantial factor in causing the plaintiff's injury or loss. In determining whether exposure to a particular defendant's silica or mixed dust was a substantial factor in causing the plaintiff's injury or loss, the trier of fact in the action shall consider, without limitation, all of the following:
1. (1) The manner in which the plaintiff was exposed to the defendant's silica or mixed dust;
2. (2) The proximity of the defendant's silica or mixed dust to the plaintiff when the exposure to the defendant's silica or mixed dust occurred;
3. (3) The frequency and length of the plaintiff's exposure to the defendant's silica or mixed dust;
4. (4) Any factors that mitigated or enhanced the plaintiff's exposure to silica or mixed dust.
(C) This section applies only to tort actions that allege any injury or loss to person resulting from exposure to silica or mixed dust and that are brought on or after the effective date of this section.