
"Could Cause Serious Human Injury"
An inept coworker of mine injured themselves attempting to bypass the lock* on a telecom room's door, by using a Phillips screwdriver to manipulate the doorlatch's tongue. The screwdriver slipped, jabbed them in the forehead, and left a cross-shaped scar.
We started referring to this person as, "Squeaky", the nickname being a reference to Alice Lynette "Squeaky" Fromme, a mentally unstable person who was a member of the Manson Family cult, and who had attempted to assassinate U.S. President Gerald Ford. Ms. Fromme had carved an "X" into her forehead, as had other members of the Manson cult.
Nearly ANYTHING "could cause serious human injury" if it's in the hands of a determined person (or in the hands of an idiot).
*They had a legitimate, job-related reason for entering that room, but the person with the keys was not reasonably-conveniently-available.