Suppressive shields, explosives

B. W. Je2ek, "Suppressive Shielding for Ha2ardous Munitions Production Operations" in Symposium on Processing Propellants, Explosives, and Ingredients, American Defense Preparedness Association (ADPA), Washington, D.C., 1977. 

King, An Overview of the Suppressive Shielding Program , Minutes of the 16th Explosives Safety Seminar, Vol 1, DOD Explosives Safety Board (Sept 1974), 91 — 139 9) I. Forsten,... 

Most gas pressure parameters for vented HE explosions apply for open vents and the special venting configurations developed for suppressive shields (Refs. 17 and 19). If vents are covered with blowout or frangible covers, the peak gas pressures are essentially the same as in unvented structures, but venting times and gas impulses can be altered (increased), depending on the vent area, mass per unit... 

R.G. Thresher, Suppressive Shielding of Explosive Facilities , Proceedings of the Sixth International Pyrotechnic Seminar, Univ of Denver (July 1978), 273-303 77) H. Treu-... 

A relatively new concept called suppressive shields is offered to provide protection to the area surrounding hazardous work with pyrotechnic and explosive material. At present, these operations are either limited to small quantities, widely dispersed, or segregated by barricades. Suppressive shields provide an alternative in the form of a vented steel enclosure. 

The Group 6 Shield illustrates a unique spherical design which is small and portable for use with laboratory quantities of primary explosives. The Group 5 Shield demonstrates the modular design concept that makes suppressive shields an attractive alternative to inflexible concrete barricades. 

As this table indicates, suppressive shields are approved for use in hazardous operations involving explosive charge weights up to the equivalent of 57 pounds 50/50 pentollte for Group 5 and 50 pounds of lllumlnant mix for Group 5. 

A relatively new concept is presented for protection to the area surrounding hazardous work with explosives. Suppressive shields are vented composite steel structures which are designed to confine all fragments from an accidental detonation and to suppress hazardous blast and flame effects to a safe level. 

Department of Defense Explosives Safety Board has approved five groups of suppressive shields for protection of munitions production operations in US Army Ammunition Plants. Safety approved shields encompass seven different designs which range in size from a two foot diameter steel shell (Shield Group 6) to a ten foot diameter steel cylinder (Shield Group 3). 

Studies have been conducted to develop a technological base for accurate determination of shield performance parameters. It was found early in the program that the available data base was inadequate for accurately predicting the blast, fire, and fragment effects that would occur as a result of an accidental detonation of an explosive in a shield environment. Indepth studies resulted in development of suppressive shield design procedures... 

Suppressive Shield When Subjected to an Internal Explosion, Minutes of the 17th Explosive Safety Seminar, Denver, Colorado, September I976. (U)... 

Hublch, H.O. and Kachinskl, R.L., Explosive Waste Removal Systems for Suppressive Shields, EM-CR-76002, Edgewood Arsenal, Aberdeen Proving Ground, Md., August 1975- (U)... 

Optical detectors shall be used in more open configurations where ressure buildup due to the incipient explosion is limited. Optical etectors shall not be used where high dust concentrations limit the reliability of the suppression system. Both uv and ir detectors are available for optical detection. The use of daylight-sensitive sensors shall be avoided to avoid spurious activation. The sensor shall be mounted such that the angle of vision allows it to cover all the protected hazard area. The performance of an optical detector will also be affected by any obstacles within its vision, and this shall be overcome by the introduction of more detectors. Optical detectors shall be fitted with air shields to keep the optical lens clean. 

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