Mine-Protected Vehicles (MPVs) are sometimes called Mine-Proof Vehicles. This is not true. No vehicle is Mine-Proof because there is no limit to how much explosive there might be in a mine. Enough explosive will throw any vehicle high into the air, and the heavier its armour, the more crushing the landing will be.
Conventional vehicles like the 4x4 ambulance shown below are not “mine-protected” by design, but they still offer some protection against small devices.
For example, a PMN (240g TNT) detonation beneath the wheel of any 4x4 will not usually result in injury to an occupant – although the vehicle may go out of control and crash causing injury. I do not know of any cases where an AP blast mine detonating under a wheel caused a fire, but they may have occurred. With larger mines, the results of a detonation under an unprotected vehicle can be devastating. The unprotected 4x4 vehicle below hit an AT blast mine and its long-range diesel tanks ruptured and burned…
Just as the thin bodywork of a conventional car can protect against a small blast, so it may stop or deflect fragmentation from small devices, or from larger devices a long way away.
The weakest point of a standard vehicle is the glass. When struck by fragments it may shatter or simply be penetrated. When struck by sufficient blast it will shatter and each bit of glass will become a sharp edged fragment moving at high speed.
MPVs have to protect their occupants against both Blast and Fragments. These are very different threats. Let me illustrate this. A flexible Kevlar armour is put inside the door panel of a conventional Toyota 4x4. It can stop a rated calibre of rifle ammunition at a set distance with complete reliability, so it will stop fragments from standard fragmentation mines… But just down the road a large blast is initiated alongside the vehicle. The door with its fragmentation panel is not penetrated. It is flattened and driven sideways, squashing you against the opposite door and moving both doors 100 metres sideways with what is left of you wedged in between. The armour worked, but provided no protection.
A good MPV will also protect its occupants against blast overpressure (generally a problem when blast forces get in and cannot readily get out of the passenger area) and heat (associated with the detonation but also with any resultant fire).
Protecting against blast
Protecting against fragmentation
Protecting against shaped charges
The survivability of materials
Bolt on armour plates
Blast (ballistic) blankets
Real Mine Protected Vehicles (MPVs)