Safely Incidents

Failures can either be fail-safe or fail dangerously. Fail safe incidents may be initiated by spurious trips that may result in accidental shutdown of equipment or processes. Fail dangerously incidents are initiated by undetected process design errors or operations, which disable the safety interlock. The fail dangerously activation may also result in accidental process liquid or gas releases, equipment damage, or fire and explosions. 

Safety leadership -Number of lessons from safely incidents communicated to persoimel -Time devoted to safety in management meetings -Weekly management safety walks (visits) -Potential risks are systematically considered when making management decisions... 

The economic impact of a spurious or nuisance trip of an ESD system can be disastrous. An ESD system is an important layer of protection to prevent and prevent hazardous situations from occurring. So, it is needless to mention that the ESD system must be extremely reliable and function on demand. During an emergency, it must put the process in a safe state in orderly fashion. Also ESD systems design shall be based on a fail safe independent system, that is, ESD systems are such that during a failure of a component the process reverts to a condition considered safe and not a vulnerable serious hazardous event. Reliability and availability are major parameters for ESD system performance. Reliability is a function of system failure rate (its reciprocal) and mean time between failures. Spurious trip conditions may initiate a so-called fail safe incident that may result in accidental shutdown of equipment or processes. However, undetected process design errors or operations may initiate dangerous incidents that may disable the safety interlock and may even cause accidental process... 

In 1982, seven people died from consuming cyanide-laced Tylenol capsules. The incident resulted in a total product recall, massive negative pubHcity for the product, new requirements for safe packaging, and a federal statute making product tampering a crime (2). Since that time, the packaging industry has become visible to most consumers. This awareness has benefited the consumer by a reduction in loss of life due to consumption of adulterated products from tampering. Never before has an industry reacted so swiftly to resolve a problem. 

Cardiac arrhythmias are an important cause of morbidity and mortality approximately 400,000 people per year die from myocardial infarctions (MI) in the United States alone. Individuals with MI exhibit some form of dysrhythmia within 48 h. Post-mortem examinations of MI victims indicate that many die in spite of the fact that the mass of ventricular muscle deprived of its blood supply is often quite small. These data suggest that the cause of death is ventricular fibrillation and that the immediate availability of a safe and efficacious antiarrhythmic agent could have prolonged a number of Hves. The goals of antiarrhythmic therapy are to reduce the incidence of sudden death and to alleviate the symptoms of arrhythmias, such as palpitations and syncope. Several excellent reviews of the mechanisms of arrhythmias and the pharmacology of antiarrhythmic agents have been pubflshed (1,2). 

Eluoride added to a compatible dentifrice base at a level of 1000 ppm has been clinically proven to reduce the incidence of dental caries by about 25% on average, even in areas where the water supply is fluoridated (4). Elevation to 1500 ppm increases the protection. Sources of fluoride approved for use in dentifrices are sodium fluoride [7681-49-4] (0.22%), sodium monofluorophosphate (0.76%), and stannous fluoride [7783-47-3] (0.41%). The Eood and Dmg Administration regulates fluoridated dentifrices as dmgs and has estabUshed parameters for safe and effective products. CompatibiUty of the fluoride with the abrasive is an important requirement. 

The goal at the first responder awareness level is to provide those persons, who in the course of their normeil duties may be the first on the scene of a hazardous materials incident with the following competencies to help them act in a safe manner when confronted with a hazardous materials incident... 

The goal at the first responder operational level is to provide the designated first responder with the following competencies to respond safely to the incident... 

Injection—The injection of hazardous materials into the body sounds, at first, like a bad joke. Who in his right mind would inject themselves—exp>ecially when it is not required by a doctor However, it can occur by stepping on or bumping against a sheup object while working at an incident site. It will happen before you even realize it has occurred and the reality of possible being internally contaminated sinks in. The best precaution for this eventuality is to have on protective clothing and observe safe work habits. 

Occasionally, however, it may be impossible to be certain that a piece of equipment is spotlessly clean, especially if it has contained a residual oil or a material that polymerizes. If this is the case, or if there is some doubt about its cleanliness, then the hazards and the necessary precautions should be made known to the workshop or the other company. This can be done by attaching a certificate to the equipment. This certificate is not a work permit. It does not authorize any work but describes the state of the equipment and gives the other company sufficient information to enable it to carry out the repair or modification safely. Before issuing the certificate, the engineer in charge should discuss with the other company the methods it proposes to use. If the problems are complex, a member of the plant staff may have to visit the other company. The following incidents show the need for these precautions. 

The report on the incident states Our reading of the literature led us to believe that as long as the leaking gas could be relieved through the weep holes, it would be safe to operate the equipment. We called a number of knowledgeable people and discussed the safety issue with them. Consensus at the time supported our conclusion. But after the explosion, there was some dispute over... 

In another incident the nitrogen flow was too small. The range of the rotameter in the nitrogen line was 0-60 L/min (0-2 fC/min) although 150 L/min (5 ft /min) was needed to keep the oxygen content at a safe level. 

Safe operation for many years does not prove that a reaction will not run away. Unknown to the operators, the plant may be close to the conditions under which it becomes unstable, and a slight change in pressure, temperature, or concentration, too small to cause concern, may take it over the brink. The operators are blind men walking along the edge of a precipice, as the following incidents illustrate. 

The value of TNT equivalency A value based on an average deduced from observations in major incidents or a safe and conservative value (whether or not dependent on the presence of partial confinement/obstruction and nature of the fuel). 

To express the maximum potential explosive power of a fuel, a safe and conservative value for TNT equivalencies of vapor cloud explosions was estimated from literature data on major incidents, after correction for virtual distance. Prugh (1987) concluded that the maximum energy-based TNT equivalency is highly depen-... 

The successes of the traditional approach have largely been obtained in the area of occupational safety, where statistical evidence is readily available concerning the incidence of injuries to individuals in areas such as tripping and falling accidents. Such accidents are amenable to behavior modification approaches because the behaviors that give rise to the accident are under the direct control of the individual and are easily predictable. In addition, the nature of the hazard is also usually predictable and hence the behavior required to avoid accidents can be specified explicitly. For example, entry to enclosed spaces, breaking-open process lines, and lifting heavy objects are known to be potentially hazardous activities for which safe methods of work... 

Explosive Incidents. Incidents which have involved mixts with perchloric ac which are normally safe, but which have expld as a result of unusual circumstances or mishandling ... 

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