Blast suppression

ANALYSIS - SCALING LAWS COMPUTER CODES - BLAST SUPPRESSION DYNAMIC STRESS ANALYSIS - STRUCTURES FABRICATION AND TESTING COST EFFECTIVENESS ANALYSIS ENGINEERING SUPPORT... 

The tent-and-foam system consists of an inner tent filled with blast suppressive foam, an onter ballistic tent, and an integrated air pollution control system. The tent-and-foam system is designed to contain the blast, fragments, and toxic emissions resulting from the detonation of a chemical munition using 5 pounds of donor explosive for every pound of chemical agent fill. 

Explosion calculations, 499-504 Estimating destruction, 501 Overpressure, 502 Pressure piling, 501, 504 Relief sizing, 505 Scaled distance, 502, 503 Schock from velocity, 503 TNT equivalent, 499-504 Explosion characteristics of dusts, 515 Explosion suppression, 518 Explosion venting, gases/vapors, 504 Bleves, 504 Explosions, 482 Blast pressure. 496 Combustion, 482 Confined, 482 Damage, 498-501 Deflagration, 482 Detonation, 483... 

Typical sections through vent panels evaluated in the suppressive shields program are shown in Fig. 36, together with definitions of vent area ratios which were found to correlate with attenuation of transmitted blast waves. 

Esparza, E. D., Baker, W. E., Oldham, G. A., "Blast Pressures Inside and Outside Suppressive Structures," Report EM-CR-76042, Edgewood Arsenal, Aberdeen Proving Ground, MD., 1975. 

WARNING Administer only under sup vision of a healthcare provider experienced in leukemia and in an institution w/ resources to maintain a pt compromised by drug tox Uses Acute leukemias CML in blast crisis, breast CA Action DNA intercalating agent i DNA topoisom ases I II Dose (Per protocol) 10-12 mg/mVd for 3-4 d 4- in renal/hepatic impairment Caution [D, -] Contra Bilirubin >5 mg/dL, PRO Disp Inj 1 mg/mL (5, 10, 20 mg vials) SE X BM, cardiotox, N/V, mucositis, alopecia, IV site Rxns, rarely -1- renal/hepatic Fxn Interactions Myelo-suppression W/ antineoplastic drugs and radiation therapy -1- effects OF live virus vaccines EMS Monitor for S/Sxs of Infxn OD May cause N/V, t Infxn risk and cardio/GI tox symptomatic and supportive... 

Mechanism of Action Inhibits Bcr-Abl tyrosine kinase, an enzyme created by the Philadelphia chromosome abnormality found in patients with chronic myeloid leukemia (CML). Therapeutic Effect Suppresses tumor growth during the three stages of CML blast crisis, accelerated phase, and chronic phase. 

The first attempts to reduce the temperature of detonation products of the explosive, and the second introduces flame-suppressing materials at and near, the face where blasting... 

A somewhat different application of foam is in blast and fire suppression during attempts to deactivate, or intentionally destroy, suspected terrorist bombs. When such a device, or even a small explosive device used to destroy the suspected item, explodes, severe damage can be caused by the compression wave emanating from the blast or from the fireball that may follow the blast. In Section 9.6 it was mentioned that foam blankets have been developed for blast noise and pressure wave... 

The next step is to develop procedures to predict suppression of blast, fragment, and flame hazards. The nature of the suppression governs the magnitude of the loads imposed on the structure. A safe, economical shield must be designed to withstand loads imposed. Suppression and design tradeoffs are made to obtain the best shield which satisfies hazard suppression requirements to provide a safe environment at minimal cost. 

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. 

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... 

Esparza, E.D., Baker, W.E., and Oldham, G.A., Blast Pressures Inside and Outside Suppressive Structures, EM-OR-7604 2,... 

Schumacher, R.N., Kingery, C.N., and Ewing, W.O., Jr., Air-blast and Structural Response Testing of a lA Scale Category I Suppressive Shield, BRL Memorandum Report No. 

The blasting device ruptures a restraining diaphragm, causing the release of suppression agent which is under 600 psi dry nitrogen pressure. 

Pefloxacin in suprabactericidal concentrations (2.0 mg/ml and 0.4 mg/ml) markedly suppressed T Ijmphocyte pro-hferation in blast transformation 0.08 mg/ml did not (7). Pefloxacin in a maximal effective dose (200 mg/kg) suppressed delayed hypersensitivity skin reactions in mice. 

Development of ethylene [64] starts about 40-60 min after mechanical perturbation, much earlier than generation of salicylic acid [53]. This perturbation is induced, for instance, just by wind [30], explaining the observation that the rice blast disease (induced by pathogens) is suppressed in seasons of strong wind (apparently the perturbation induces expression of ethylene, this stimulates generation of phytoalexins which prevent attack by fungi). 

According to Kaye 5l currently much in use arc laced concrete walls (Fig. 131) forming a shock wave barrier, but more modern designs are those of suppressive structures. They are made of new suppressive structures of several layers of louvered and perforated plates of angle iron and z bars. This allows controlled release of blast effects from a detonation within the structure. Subsequently a controlled release of blast effects occurs. 

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