The Threat

A chemical or biological attack or incident won t always be immediately apparent given the fact that many agents are odorless and colorless and some cause no immediately noticeable effects or symptoms. Be alert to the possible presence of agent. Indicators of such an attack include  

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Implantable valves, particularly mechanical valves which continue to encroach on tissue valves, are unique. Methods such as valvuloplasty, mitral valve repair, or use of ultrasound are unlikely to reduce the number of valve replacements into the twenty-first century. Valve selection remains in the hands of the surgeon because of the critical nature of the procedure. If anything goes wrong, the result can be catastrophic to the patient. Cost of a valve, from 3000— 4000, is a relatively small part of the cost of open-heart surgery which can mn as high as 30,000. Growth of the cardiovascular valve market has slowed in the United States with the decline of the threat of rheumatic fever. 

The threat of accidental misuse of quaternary ammonium compounds coupled with potential harmful effects to sensitive species of fish and invertebrates has prompted some concern. Industry has responded with an effort to replace the questionable compounds with those of a more environmentally friendly nature. Newer classes of quaternaries, eg, esters (206) and betaine esters (207), have been developed. These materials are more readily biodegraded. The mechanisms of antimicrobial activity and hydrolysis of these compounds have been studied (207). AppHcations as surface disinfectants, antimicrobials, and in vitro microbiocidals have also been reported. Examples of ester-type quaternaries are shown in Figure 1. 

Most anthraquiaone dyes and their iatermediates are handled ia a powder form. Their dust poses the threat of coatact to eyes and skin or contamination of surroundings. Attention must be paid to avoid these ha2ards. Special attention should be paid to avoid contact with compounds that are recogni2ed to have probable carciaogenicity. 

Instrumentation (Arthur D. Little, Inc., and Levine, 1986.) Instrument systems are an essential part of the safe design and operation of systems for storing and handling highly toxic hazardous materials. They are key elements of systems to eliminate the threat of conditions that could result in loss of containment. They are also used for early detection of releases so that mitigating ac tion can be taken before these releases result in serious effects on people in the plant or in the public sector, or on the environment. 

People will tolerate a greater level of risk if the threat is one they specifically have chosen to accept (mountain climbing, flying, etc.). Individuals reject comparable risk if the risks are imposed upon them (e.g., a landfill springing up in a hitherto vacant lot beside a house). 

Most people will tolerate greater risk from activities when the threat to life is offset in time from when the risk (and the benefit) is originally accepted. For example, people may feel worse (and usually accept less risk) about a threat of immediate harm (e.g., the blast wave from an explosion) than a threat of latent harm (e.g., an increase in the chance of getting a fatal disease following a 20-year exposure to a hazardous material, like asbestos), even though the risks may be equivalent. 

Dry gas seals operate under extremely tight toleranees, whieh demand that speeial eare be taken in the design of the gas seal environment, and in the operation of the eompressor and gas seal system. While the threat of seal degradation and redueed seal life due to outside influenees is real, the detrimental effeets of these faetors ean be minimized. 

There is a written procedure for condenser isolation, but it is normally a simple step-by-step task that is second nature to the operator and is performed from memory. However, imder the threat of a potential vapor cloud explosion, the operator may forget to close the propane valves first (Error A). The HEP in Handbook Table 20-7 5 footnote (.01) is increased by a factor of 5 per Handbook Table 20-16 6a to account for stress. 

Recognition of the threat of stratospheric ozone depletion posed by chlorofluorocarbons and chloro-fltiorohydrocarbons led 131 countries to sign the Montreal Protocol in 1987. Production of chlorofluorocarbons was banned as of January 1, 1996, because of their potential to further deplete stratospheric ozone. Chlorofluorohydrocarboiis will be... 

Always call 911 first to assure that first responders are dispatched to the scene to stabilize the release, render first aid, establish a perimeter, and extinguish/minimize the threat of fire or explosion. 

ADRENAL INSUFFICIENCY. Administration of the glucocorticoids poses the threat of adrenal gland insufficiency (particularly if the altemate-day therapy is not prescribed). Administration of glucocorticoids several times a day and during a short time (as little as 5-10 days) results in shutting off the pituitary release of ACTH... 

Chong AK, Pegg MS, Taylor NR, von Itzstein M (1992) Evidence for a sialosyl cation transition-state complex in the reaction of sialidase from influenza virus. Eur J Biochem 207 335-343 Cinatl J Jr, Michaelis M, Doerr HW (2007a) The threat of avian influenza A (H5N1). III. Antiviral therapy. Med Microbiol Immunol 196 203-212... 

Sterilization is an essential stage in the processing of aity product destined for parenteral administration, or for contact with broken skin, mucosal surfaces or internal organs, where the threat of infection exists, hi addition, the sterilization of microbiological materials, soiled dressings and other contaminated items is necessary to minimize the health hazard associated with these articles. 

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