Bomb suit
A bomb suit, Explosive Ordnance Disposal (EOD) suit or a blast suit is a heavy suit of body armor designed to withstand the pressure generated by a
Parts of the bomb suit overlap for maximum protection. The suit protects in several different ways. It deflects or stops projectiles that may come from an exploded device. It also stops or greatly decreases the pressure of the blast wave being transmitted to the person inside of the suit. Most bomb suits, such as the Advanced Bomb Suit, use layers of Kevlar, foam, and plastic to accomplish these functions.
In order to maximize protection, bomb suits come with a pair of interchangeable gloves and wrist guard attachments. This gives the wearer's hands mobility and protection needed for the task and avoid cross contamination of any evidence found (e.g., fingerprints).
History
Modern day EOD units had their beginnings in World War II, when the German Luftwaffe greatly increased the number of bombs dropped on British soil. As the number of civilian casualties grew due to delayed explosion of bombs, which had often penetrated several feet into the ground after being dropped from planes, men were trained to defuse the unexploded devices and groups were dedicated to try to keep up with that task.[4] As fuse designs changed, many of these early UXD (unexploded device) soldiers died until more successful means to defeat a new design were developed.
As the United States saw its likely involvement in World War II, they requested help from the British to train a civilian EOD force that could defuse unexploded bombs in urban areas. The human cost of learning the variety of fuses and how to defeat them was lower for the U.S. due to this education. After it became clear that EOD tasks were best handled by the military, the U.S. tried several ways to organize EOD personnel that would allow for the need for both specialized training and diverse deployment.[5][6]
In photos of early missions to defuse unexploded bombs,[7] the men are not wearing any protective gear. In fact, they are often shirtless to cope with the heat generated by the manual labor of digging around the devices before they could be defused. Basically, the individual defusing the bomb succeeded - or died.
The first EOD suits consisted of
The threats posed by an Improvised Explosive Device, commonly known as an
In 2006, the U.S.
Developers must consider more than just protection, since a person must work on a stressful task that also requires fine motor skills while wearing a bomb suit. Other factors that must be considered include
- cushioning the spine and head in case the wearer is knocked over by a blast
- thermal heat protection[1]
- freedom of motion to work efficiently[1][2][3]
- maximum weight restrictions
- rapid removal, such as for emergency medical treatment
- defogger performance to prevent the helmet visor from clouding
Protection
The pieces of a bomb suit overlap with other pieces for maximum protection from the front and minimal protection for the back and sides from an explosive device. The suit protects in several ways. It deflects or stops projectiles that may come from an exploded device. The second way it protects is by stopping the blast wave from being transmitted and injuring the wearer. Usually, Kevlar, foam, and plastic are layered and covered with fire retardant materials to accomplish these things. It is important that the fibers are strain-rate sensitive, or become more rigid if struck by an object traveling at high speeds, according to a ballistics engineer working for bomb suit manufacturer HighCom Security.[10]
Until the mid-1990s, EOD suits consisted of Kevlar and/or armor plates to stop projectiles. However, the suits did not offer much protection against the blast wave itself. The most recognized injury due to the blast wave is called “blast lung.” The lungs (and other internal organs) can be injured by the blast wave and bleed, even when there is no penetrating injury; such internal injuries can be fatal. In the mid-1990s, research conducted in the UK showed that textile and rigid plate armor by themselves do not protect the lungs from blast injury.[8] It was found that a layer with high acoustic impedance with a backing of a softer, low-acoustic impedance layer (such as low density foam) would protect from blast injury. However, it was also shown that it is important to understand the frequency content of the applied blast wave and to experimentally test the way materials are put together to make sure they are effective.
Ergonomic issues
To effectively stop a blast wave, thick layers of Kevlar, foam and plastic are needed to prevent serious bodily harm. Since the entire body needs protection, the resulting bomb suit is heavy (80 lb (36 kg) or more), hot to the point of risking
The materials needed to make bomb suits protective do not release body heat generated by the wearer.[1] The result can be heat stress, which can lead to illness and disorientation, reducing the wearer's ability to accomplish the task.[1][2][3][11] The most recent models of bomb suits include battery-operated cooling systems to prevent heat stress. One manufacturer's study claims that the internal cooling systems on 39 to 81 lb (18 to 37 kg) bomb suits helped the wearer stay at workable temperatures for up to an hour, even in a hot environment.[12]
See also
- Anti-handling device
- Clearance diver
- Counter-IED efforts
- Fuse (explosives)
- Overpressure
- 52nd Ordnance Group (EOD)
- EOD CoE
- Explosive Ordnance Disposal Badge
- GeganaIndonesian police bomb disposal specialists
- Navy EOD
- TEDAX Spanish bomb disposal organisation
References
- ^ PMID 24586228.
- ^ PMID 25878167.
- ^ PMID 25866818.
- ^ A short history of Royal Engineer Bomb Disposal Archived 2003-10-02 at the Wayback Machine posted by The Royal Engineers Bomb Disposal Officers Club (U.K.), accessed 26 July 2011.
- ^ A short history of the beginnings of the U.S. EOD Archived April 2, 2012, at the Wayback Machine posted by the National EOD Association, accessed 26 July 2011.
- ^ A short history of American EOD Archived 2011-10-04 at the Wayback Machine recounted by The Origins of U.S. Army Explosive Ordnance Disposal by CSM James H. Clifford (Ret.), accessed 26 July 2011.
- ^ see, for example, A WWII bomb disposal case history, accessed 30 July 2011
- ^ PMID 8606389.
- ^ Waclawik, S. Explosive Ordnance Disposal Personal Protective Equipment (EOD PPE) Standard. Presentation by the Ballistic Technology Team, Natick Soldier Center, Natick, Massachusetts, USA. read online
- ^ "Real-life Hurt Locker: how bomb-proof suits work". dvice. Retrieved October 25, 2013.
- ^ Stewart, Ian B.; Rojek, Amanda M.; Hunt, Andrew P. Heat Strain During Explosive Ordnance Disposal. Military Medicine, Volume 176, Number 8, August 2011, pp. 959-963.
- ^ Thake, C.D., et al., A thermal physiological comparison between two Explosives Ordnance Disposal (EOD) suits during work related activities in moderate and hot conditions. read online
External links
- Development of a Bomb Suit Standard, U.S. Army Natick Soldier RD&E Center
- 360° view of a Clearance Diverwearing a bombsuit at DefenceJobs.gov.au
- This article incorporates public domain material from websites or documents of the United States Army.
- Bass et al., 2006, Comparative testing of effectiveness of different helmet/shield designs at reducing head acceleration due to blast.
- Bass et al., 2005, A methodology for assessing blast protection in explosive ordnance disposal bomb suits.