Passive restraints

This completely automated spectrum analysis procedure represents the final element in our effort to reduce to routine practice the quantitative analysis of similarly constituted gaseous samples by FTIR. It has seen wide and successful application within our laboratory, having been the principle analytic method for two extensive hydrocarbon species-specific auto exhaust catalyst efficiency studies, a comprehensive study of the gases emitted by passive-restraint air bag inflators, several controlled furnace atmosphere analyses, several stationary source stack emission checks and several health-related ambient atmosphere checks. 

The basic idea of the airbag as a passive restraint system in a motor vehicle was already patented for the first time in Germany in 1951. 

The equilibrium constant and equilibrium yield are independent of whether or not a catalyst is present. If the catalyst does not remove any of the passive restraints that have been placed on the system by opening up the possibility of additional reactions, the equilibrium yield will not be affected by the presence of this material. 

In engineering,pflsvzvc controls are those that maintain safety by their presence— basically, the system fails into a safe state or simple interlocks are used to limit the interactions among system components to safe ones. Some examples of passive controls that maintain safety by their presence are shields or barriers such as containment vessels, safety harnesses, hardhats, passive restraint systems in vehicles, and fences. Passive controls may also rely on physical principles, such as gravity, to fail into a safe state. An example is an old railway semaphore that used weights... 

D. J. Reinkensmeyer, B. D. Schmit, and W. Z. Rymer (1999), Assessment of active and passive restraint during guided reaching after chronic brain injury. Annals of Biomedical Engineering 27 805-814. 

ECONOMICS OF MANDATORY PASSIVE RESTRAINTS BENEFIT-COST ANALYSIS, RULEMAKING AND COURT DECISIONS... 

Economics of Mandatory passive Restraints Benefit-Cost Analysis, Rulemaking and Court Decisions... 

From the outset attempts were made to introduce new technology for occupant protection in the form of passive restraints. In July 1969 an advanced notice of Proposed Rulemaking entitled Inflatable Occupant Restraint Systems introduced the idea of air bags which would inflate during an accident to cushion occupants during the second collision between the occupant and the inside part of the car. The attractive feature of this safety device is that an individual can be passive since no action such as buckling is required of the occupants. A passive restraint standard was issued in 1971 but was overturned by the court until a suitable dummy could be developed for testing the performance of the restraints. 

The Coleman Rule called for a continuation of mandated safety belt installation but created a demonstration program to familiarize the public with passive restraints. Contracts were negotiated with four manufacturers for 500,000 cars equipped with passive restraints for model years 1980 and 1981. The rationale for the program was that passive restraints were technologically feasible, could be effective in reducing traffic deaths and injuries and could be produced at a reasonable cost. The rationale for not mandating passive restraints was threefold ... 

Passive restraints are more costly than other safety equipment, and the public deserves a better documented case for costly standards than with mexpensive standards especially when some occupants would be giving up active safety belts which are known to work well. 

There may be increases in the voluntary consumer demand for passive restraints due to the demonstration program. There was also the possibility that use of active safety belts might increase making passive restraints redundant. 

With the change in administration incoming Secretary of Transportation Brock Adams abandoned the Coleman Rule on the bases that public acceptance is not part of the traffic safety mandate, passive restraints clearly will be effective in improving traffic safety and the cost of the restramts will be more than offset through savings on insurance premium payments. In June 1977 under the Adams Rule, passive restraints were mandated for standard and luxury cars by the 1982 model year, for intermediate and compact size cars by the 1983 model year, and for subcompact and mini-size cars by the 1984 model year. The Adams Rule survived congressional and judidal review. ... 

BENEFIT-COST STUDIES OF MANDATORY PASSIVE RESTRAINTS... 

A sketch of an exemplary study illustrates what should be contained in a benefit-cost analysis of mandatory passive restraints if it is to be useful ... 

The first independent attempt to estimate conventionally the benefits and costs of mandatory passive restraints was made by Richard Amould and Henry Grabowski. For the reduction in fatalities and injuries in crashes they use two sets of estimates. One set is based on a 1981 field team study of rural traffic accidents which shows, for example that fatalities are reduced by 34 percent by air bags and lap belts together, 32 percent by lap and shoulder belts together, 28 percent by passive belts, and 25 percent by air bags alone. The field study estimates are only appronmately one half of the NHTSA lab study estimates which is the other set. Arnould and Grabowski assume that 60 to 70 percent of occupants with passive belts would use them and that 0 to 20 percent of occupants with air bags would also use lap belts. Occupant protection is assumed to have no affect on chances of accidents. The 1 5 distribution of traffic accident injuries and the estimates of restraint effectiveness in crashes are used to calculate the fatalities and injuries prevented. 

Nordhaus also analyzes the benefits of alternatives to the Adams Rule which calls for large car first phase-in of passive restraints. These alternatives are simultaneous installation of passive restraints in cars of all sizes, reversal of the phase in so that small cars have passive restraints first, and rescission. Of these the small-car-first alternative has slightly larger net benefits than the Adams Rule, or simultaneous installation and much larger net benefits than rescission. 

The major features of the four benefit-cost analyses discussed are summarized in Table 4-1. While differences exist, they share a common result. We might offer a conclusion based on these conventional benefit cost studies that the mandatory passive restraints poli<7 as described in the Adams Rule passes the social net benefit test. 

Recall that an exemplary benefit-cost analysis of mandatory passive restraints should reflect changes in the chances of survival in accidents and any changes in the chances of accidents. The analysis should reflect costs of installation of equipment and any increases m operation costs borne by vehicle users. The general problem with the studies reviewed is that they have taken a technological approach to traffic safety. An individual net benefit approach, which is consistent with the exemplary sodal benefit-cost analysis, suggests two critical areas of inadequaqr. The studies fail to incorporate estimates of changes in chances of accidents due to motorist response and user costs of passive safety belts associated with discomfort and inconvenience. 

The upward bias is inherent in a technological approach to traffic safety. The rigid approach caused problems in measuring the contribution of vehicle safety regulation export and it causes problems for evaluating mandatory passive restraints ex ante. The individual net benefit approach is a better approach because it incorporates zero risk compensation as a special case and permits attempts to measure any risk compensation. 

A complicating interaction not considered analysis is how passive restraints affect other components of traffic safety policy. Conventional procedures treat policy components as having isolated, independent impacts on effectiveness in... 

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