Plaintiffs Seek Exclusion of MSA Expert's Opinion on 3M Masks

ST. LOUIS - Plaintiffs in a Missouri silica case have moved to exclude testimony from an industrial hygiene expert retained by Mine Safety Appliances to offer criticism of 3M respirators that also allegedly failed to protect them from inhaling silica dust. Scaggs v. 3M Co., et al., No. 08-1163 (E.D. Mo.).

The motion to exclude James C. Johnson, Ph.D.'s expert testimony regarding 3M's 8710 and 8715 respirators as ipse dixit was filed in a series of silica cases pending in U.S. District Court for the Eastern District of Missouri and contends that Johnson's opinion is unsupported by evidence.

MSA has …