Safety quantitative measures

However, in the early stages of design, decisions that have important safety implications must be made based on an incomplete picture. Let us explore simple quantitative measures which can be used to assist decision making in the early stages of design. 

It will be apparent from the discussions in the previous sections that an absolute value of reliability is at best an educated guess. However, the risk of failure determined is a quantitative measure in terms of safety and reliability by which various parts can be defined and compared (Freudenthal et al., 1966). In developing a reliable product, a number of design schemes should be generated to explore each for their... 

The quantitative measurement of toxicity level is expressed by parameters like NOEL (no observed effect level), NOAEL (no observed adverse effect level), and ADI (acceptable daily intake). The NOEL values are divided by 100 to obtain ADI values. The 100 safety factor derives from 10 x 10, where the 10s represent the animal-to-human conversion rate and the human variability factor. Currently, the most useful index of safety is the ADI, expressed as milligrams of test substance per kilogram of body weight (ppm), with the recommendation not to eat more than the ADI per day. The FDA, EU, and WHO agree on the ADI principle. 

The What-if, the checklists and Hazop are well publicized hazard identification tools. But as Bollinger et al. (1996) have pointed out the use of any of these techniques demands knowledge, experience and flexibility. No prescriptive set of questions or key words or list is sufficient to cover all processes, hazards and all impacted populations. Bollinger et al. find that refinement of the quantitative measurement techniques such as safety indices and convergence to a single set of accepted indices would be beneficial. 

The available regulatory quantitative measures are published by the government agencies with the responsibility of safeguarding health and safety. The FDA was established in 1938, to inspect food for humans and animals, drugs, medical devices, and cosmetics. The EPA was established in 1970, to protect human health and the environment, with... 

Presently there is no direct quantitative measure of the probability of occurrence of an incident, or in the case of thermal process safety, of the occurrence of a runaway reaction. Nevertheless, if we consider the runaway curves presented in Figure 3.3, the two cases presented are very different. In case 1, after the temperature increase due to the main reaction, there is enough time left to take measures to regain control or recover a safe situation. If we compare the probability of runaway in both cases, it becomes clear that the probability of triggering the runaway is higher in case 2 than in case 1. Thus, while we cannot easily quantify probabilities, we can at least compare them on a semi-quantitative scale. 

Since the formation of the Nuclear Decommissioning Authority (NDA) there has been an emphasis on a demonstrable process for prioritisation of remediation work on UK decommissioning sites. As part of this process, the HI has now been re-named the Radiological Hazard Potential (RHP) and is one of five metrics which are combined numerically to produce a prioritisation metric, the Safety and Environmental Detriment (SED), see below. This paper relates only to the RHP. It is a quantitative measure of the potential for a material or plant item to cause harm, but does not address the risk of that harm occurring and has universal application irrespective of facility type. 

In order to carry out these measurements, we use a reaction calorimeter that was designed by Dr. L. Hub and his group in our Chemical Development Safety Lab at Sandoz Ltd., in Switzerland. It consists of a one liter reaction vessel along with the necessary equipment for temperature control and quantitative measurement of heat flow into and out of the reaction vessel. 

Strictly speaking, coefficients of friction obtained on wet surfaces cannot be called static coefficient of friction, as by accepted definition there should be nothing between the tested surfaces that might effect the friction, including water. However, as we aim at realistic slip behavior of deck surfaces, which are directly related to safety issues, in this context there is no real difference how to call the obtained values—static coefficients of friction or slip coefficients. In any case we operate with quantitative measurements of slip resistance directly applicable to realistic situations. 

This chapter explains the meaning of the above statements. It describes flammability and smoke/toxic gases evolntion at burning of wood compared to wood-plastic composite (WPC) materials and products of different compositions and profiles. It also explains flammability and fire ratings and indexes as quantitative measures for fire hazard and fire safety, and fire performance characteristics in general of wood and composites. 

Define the temperature failure criteria for the material. The producer determines experimentally the maximum service temperature his material can achieve and still provide acceptable performance. The producer determines the heat deflection temperature (ASTM D 648), Vicat Softening Temperature (ASTM D 1525), Coefficient of Thermal Expansion (ASTM D 696) or other appropriate quantitative measure of material s performance under heat. The producer then adds a suitable safety factor to the temperature determined to cause failure. 

Gui Fu, Chang-repair 2009. Corporate safety culture and its quantitative measurement study [J], China Scfety Science, 1 86-92. 

An indicator is an objective, quantitative measurement of an outcome or process that relates to performance quality. The event being assessed can be either desirable or undesirable. It is objective in that the same measurement can be obtained by different observers. This indicator represents quantitative, measured data that are gathered for further analysis. Indicators can assess many different aspects of quality, including accessibility, appropriateness, continuity, customer satisfaction, effectiveness, efficacy, efficiency, safety, and timeliness. 

Russian researchers, quoted by Shidlovsky (and undoubtedly others elsewhere), have attempted to achieve quantitative measurements from minimum and maximum distances between composition and the spit of a flame from the end of a length of safety fuse, but reproducibility seems to be poor. 

Multiple types of observational study design can be used in the quantitative measurement of risks from pharmaceutical products. Choice of a design depends on both the drug and the safety issue and should be tailored to address the specific hypotheses of interest. 

Business Metrics for Safety A Quantitative Measurement Approach to Safety Performance by Daniel Patrick O Brien, August 1998. 

Telehealthcare Issues of safety and reliability remain very important in telehealthcare. The demands of developing equipment at an appropriate level of sophistication may be especially great, for telehealthcare often requires quantitative measurement by the patient in a home environment. One of the potential benefits of telehealthcare is that it can increase the agency of patients, as they become more active in the treatment of their condition. However, such benefit may be diminished if they feel unable to cope adequately with their monitoring equipment. 

From a measmement perspective, ... safety climate can be conceived of as a snapshot , or manifestation of culture (Cox and Fhn 1998 Naevestad 2009 127-8) that can be assessed using quantitative measures, while safety culture may rather... 

Quantitative safety performance measurements can be either outcome oriented or process oriented (Daugherty 1999, 147). Outcome-oriented performance measures are after-the-fact measures. The performance activity has occurred then the results have been measured. Examples of outcome measures used in safety include the reduction in the number of accidents, lost workdays, etc. Outcome measures can provide an indication as to the impact safety program interventions have upon safety performance. These performance measures provide an historical account of the effectiveness of past performance. 

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