## Facts

- Wilson M. Hood bought a Ryobi TS-254 10-inch miter saw in Maryland for home repairs.
- The saw included an upper metal blade guard and a lower transparent guard that retracted during cutting.
- The owner’s manual and on-product decals contained multiple warnings to keep guards in place and warned that operating without guards could cause serious injury.
- The day after purchase, Hood removed the guards because the lower guard interfered with cutting a piece of lumber.
- While operating the saw without guards, the blade detached and struck Hood, partially amputating his thumb and lacerating his leg.
- Hood admitted reading the manual and most warning labels before removing the guards but claimed he did not know guard removal could lead to blade detachment.
- Hood sued Ryobi for inadequate warnings (strict liability and negligence) and for defective/negligent design.
- The district court granted summary judgment for Ryobi; Hood appealed.

## Issues

1. Whether Ryobi’s warnings were legally adequate under Maryland law even though they did not specify that removing guards could cause blade detachment.
2. Whether Hood’s design-defect and negligent-design claims could proceed where his injuries followed his intentional removal of safety guards contrary to explicit warnings.
3. Whether summary judgment for the manufacturer was proper on the warning and design claims.

## Decision

- The Fourth Circuit affirmed summary judgment for Ryobi on all claims.
- The court held the warnings were adequate as a matter of law because they clearly warned against removing guards and warned of serious injury.
- The court held the design-based claims failed because Hood’s injury resulted from his alteration and misuse of the product in direct violation of clear safety warnings.

## Legal Principles

- Under Maryland products-liability law, an adequate warning must be reasonable under the circumstances; a manufacturer need not provide “encyclopedic” detail about every possible consequence or mechanism of injury.
- Excessively detailed warnings can reduce effectiveness; the duty to warn does not require exhaustive lists that undermine communicative value.
- Clear, repeated warnings against a specific unsafe practice (here, operating without guards) can be sufficient even if they do not predict the precise accident sequence.
- A manufacturer is generally not liable for injuries caused by a user’s knowing and voluntary violation of clear safety directions; intentional removal of safety devices may constitute misuse/alteration that defeats design-defect and negligent-design theories.
- Summary judgment is appropriate where no reasonable jury could find inadequate warnings or a product defect given undisputed evidence of prominent warnings and deliberate noncompliance.

## Conclusion

The court held that multiple prominent warnings against operating the saw without guards satisfied the duty to warn despite not describing blade detachment, and that Hood’s deliberate removal of the guards constituted misuse and alteration barring his design-based claims, making summary judgment for Ryobi proper.


Hood v. Ryobi Am. Corp., 181 F.3d 608 (4th Cir. 1999)