Risk classes

Besides the class I-typical proarrhythmic risk class IA antiarrhythmics possess a marked proarrhythmic risk for the induction of torsade depointes arrhythmia (life-threatening polymorphic ventricular tachycardia observed with most action potential prolonging drugs). 

Risk Class Device Evaluation Quality System Regulations Marketing Authorisation... 

If possible, withhold for at least 5 days in patients in whom CABG is planned to decrease bleeding risk (class I recommendation)... 

The long-term widespread use of DDT over a number of years demonstrates one typical Soviet trick - abusing loopholes in the rules. DDT was actively used for decades, while not being on lists of permitted substances, a situation condoned by the Health and Epidemiological Services and their on-site agencies. Pesticide use systematically was not in accordance with the permissible standards in the USSR. In 1976 the USSR introduced a System of Labor Safety Standards Harmful Substances, Classification and Overall Safety Requirements, according to which all harmful substances were broken down into four risk classes, taking into account several different indices (table 1.5). 

According to VNIIGINTOKS, potent toxic agents (PTA), where the fated dose (FD, J is less than 50 mg/ kg, are not introduced into agriculture, are not produced in the USSR, and are not imported from abroad [12]. In actual fact, Risk Class I OPPs with an FD for laboratory animals of less than 50 mg/kg were not only actively used, but were also produced in the USSR for many years (including such OPPs as parathion, demeton, octamethyl pyrophosphoramide, methyl ethyl... 

Newborns are especially vulnerable to pesticides effects, since they do not have a fully developed immune system and adaptation mechanisms, or detoxification systems for foreign chemicals. A direct correlation between overall pesticide exposure in a given territory and primary illness in newborns [A101] was traced into even those territories of the Ukraine where the volumes of pesticides used were not extreme. The clearest expression of the pesticide exposure - primary newborn illness correlation is seen with pesticides of the second risk class (by toxicity), while the correlation is less clear for pesticides of the third and fourth categories. The most dangerous pesticides of all types for newborns are OCPs, with OPPs a close second [A101]. 

In Figure 29, the rows of both risk classification matrices show the established likelihood, while the columns show the perceived consequences. The result of both likelihood and perceived consequences is the perceived risk, which is indicated with a perceived risk class from 1 to 4 for the left risk matrix and from 1 to 3 for the right risk matrix. The interpretation of the different risk classes for the left matrix in Figure 29 is derived from the IEC 61508 (IEC 61508, 2000) and is stated as ... 

An interpretation of the different risk classes for the right matrix in Figure 29 is not made. The perceived risk is only derived for prioritizing the precursors so no interpretation is necessary. Class 1 risk means that the precursor present in this class will be analysed first, precursors in Class 2 risk, second, etc. The final decision, which precursors will be analysed further if there are more precursors belonging to the same class of perceived risk, is made by the multi-disciplinary group of experts, who established the perceived consequences. 

Prioritize precursors Prioritize the list of precursors according to their perceived risk classes. 

From Figure 32, the precursor packaging machines not empty when performing maintenance, prioritized as belonging to the first risk class, is taken as an example, to identify the controlling process for this precursor in practice and to identify the initial ineffective control element. 

The second step, of sorting the selected precursors according to their perceived safety related consequences, is achieved by studying safety reports and confronting the precursors with multi-disciplinary experts, i.e. experts from production, maintenance and safety. The expert group provided the identified precursors with perceived safety related consequences, by formulating possible scenario s, from which the consequences could be obtained. From both the likelihood (see Table 17) and perceived consequences, the perceived risk class is obtained, as discussed in Chapter 5. Figure 42 shows the risk matrix for the precursors presented in Table 17. 

In Figure 42 the different grey-scales of the cells represent the different perceived risk classes, i.e. the precursors present in the four dark grey cells are classified first, precursors present in the four grey cells are classified second and precursors present in... 

HAZARDOUS INGREDIENT NAME CAS No CONTENT RISK CLASS... 

Risk Class Stage Clinical Characteristics % At Median Diagnosis Survival (y) ... 

RISK Class NUMBER OF EMPLOYEES (E) QUALIFICATIONS OF SAFETY ENGINEER... 

Ax = reduction term for the cover thickness (mm), depending on the risk class of the structure. 

Safety factors are given for three different levels of the criticality (risk dasse of the structure high, normal and low. These classes refer to the cost of reducing the risk of premature maintenance compared to the cost of repair. In other words, the risk class is related to the desired reliability of the structure. In Table 11.13 the safety factors for chloride-induced corrosion in marine environment are given. 

Rather than building a safety margin into a single minimum attractive rate of return, some firms establish several risk classes with separate standards for each class. For example, a firm may require low-risk investments to yield at least 15% and medium-risk investments to yield at least 20%, and it may define a minimum attractive rate of return of 25% for high-risk proposals. The analyst then... 

Class I and low-to-intermediate risk Class II devices. Previously, the FDA was authorized to create standards for medical devices. The new legislation allows the FDA to recognize and use all or parts of various appropriate domestic and internationally recognized consensus standards that address aspects of safety and effectiveness relevant to medical devices. 

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