The M18A1 Claymore mine is a directional fragmentation antipersonalanti-personnel mine. It is designed to kill by projecting a lethal hail of steel balls within a 60-degree cone in front of itself.
It seems setting off an M18A1 attached to one's unprotected chest would kill or seriously injure youone. There's a "secondary missile hazard" area with a radius of approximately 100 meters from the device and a "concussion area" 16 meters around the device. Note that, while troops in the "secondary missile hazard" area are advised to take cover, no troops are allowed in the "concussion area" whatsoever. This implies that being that close to a detonating Claymore will, if not kill an unprotected person, certainly render them "combat ineffective"/heavily injured.
However, what if said person was wearing a bomb suit?
A bomb suit is armor designed to withstand pressure and fragmentation effects generated by an explosive device's detonation. Presumably, such a suit of armor - designed to protect its wearer from explosions at close to point-blank range - will at least partially mitigate the effects of a point-blank M18A1 blast wave.
So, here's the question: how safe would it be to wear a bomb suit with an M18A1 Claymore mine attached to the chest (front facing away, of course), and then detonate said Claymore?
How is this related to worldbuilding? Well, in my setting, there's something exceptionally dangerous that's really good at hiding, and it's often capable of reaching point-blank range long before humans can actually see it. As such, having an immediate defense against it is a top priority.
Moreover, bomb suits are already relatively common in this particular part of the setting, as it's under sporadic artillery barrage.