Dynamic entry

Door breaching is a process used by military, police, or emergency services to force open closed and/or locked doors. A wide range of methods are available, one or more of which may be used in any given situation.

Where no tools are available, it is usually possible to force open most inward-opening doors with a strong kick that breaks through the door frame. This can be a common method of entry for many trained police officers who are conducting warranted searches, and the "macho" concept of kicking in doors has frequently been glamorized on various police procedural shows. Kicking in a locked door is also sometimes attempted or performed by neighbors and ordinary passers-by who witness an emergency situation such as a house that is on fire (though the first step should always be to call Emergency Services) in order to ensure that everyone is out of the house or to notify/assist anyone who is not. Kicking in doors is less commonly used in burglary attempts since the process requires a great deal of energy and makes a lot of noise.

Regarding the use of specified tools for forcible entry, there are several other methods of door breaching. These methods may be divided up into mechanical breaching, ballistic breaching, explosive breaching, and thermal breaching.

Mechanical breaching can be minimally destructive, through the use of lock picks. This method is relatively slow and requires a trained operator, but does not damage the lock or door. Using specialized tools (i.e.: A-tool, K-tool), a lock cylinder can also be quickly dismantled and unlocked without removing it from the door; this method also allows the door to be closed and re-locked. Mechanical breaching also includes hydraulic breaching, which uses a special hydraulic ram to overcome the lock. The hydraulic ram may be powered manually, pneumatically, or electrically. More dynamic methods (kinetic breaching) use force to break the lock or door. The common methods are to use a lever, such as a Halligan bar or crowbar, or to use a tool to concentrate a large amount of force on the door, such as a sledgehammer, hydraulic jack, or battering ram.

Ballistic breaching uses a projectile weapon to breach an opening. Weapons used can range from small arms to the 120mm cannon of a main battle tank with a HEAT round, which will breach most obstacles easily, though the force involved may violate the rules of engagement. A less damaging ballistic breach needs to destroy either the latch and lock, or the hinges of the door, and the ideal choice for this is the shotgun. While in theory other firearms can be used, handguns are usually underpowered and rifles are less effective than the shotgun and pose a far higher risk of ricochet and collateral injury. Most shotgun ammunition can be used for breaching, though the risk of injury varies with type. Of the available shotgun ammunition, shotgun slugs pose the highest risk, as they will retain significant energy to cause lethal wounds well after they have penetrated the door. Buckshot is far safer, and birdshot even safer, as the multiple small projectiles disperse quickly after penetration, reducing the chances of causing a lethal wound. The safest option is a frangible round such as the TESAR or Hatton round, which turns to dust upon penetrating the door, and disperses completely upon exit.

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Wikipedia