Safety seven levels

The vertical intent dimension has seven levels. Each level represents a different model of the system from a different perspective and supports a different type of reasoning about it. Refinement and decomposition occurs within each level of the specification, rather than between levels. Each level provides information not just about what and how, but why, that is, the design rationale and reasons behind the design decisions, including safety considerations. 

We are now at a transitional point in the book between the understanding and analysis of incidents and the coining chapters, which discuss methods of prevention and quality improvement. The seven-levels framework has outlined the patient, task and technology, staff, team, working environment, organizational and institutional environmental factors that are revealed in analyses of incidents. These same factors also point to the means of intervention and different levels on which safety and quality must be addressed, which we will explore systematically as the book unfolds. 

Charles Vincent has explored seven levels of safety as a leadership framework for analyzing risk and safety in medicine (see Raef, 2002). The seven levels are the following ... 

These seven levels help to identify patterns in risk and safety and can aid in directing the appropriate level of intervention. Vincent also suggests four diagnostic questions for choosing safety interventions (see Raef, 2002, p. 3) ... 

The chaotic situation existing in the synthetic colorant industry was evident in the 80 colorants available in 1907 to the paint, plastic, textile, and food industries. Obviously very few of them had been tested for safety. Dr Bernard Hesse, a German dye expert employed by the US Department of Agriculture, was asked to study the situation and he concluded that, of the 80 colorants available, only 16 were more or less harmless and he recommended only seven for use in food. This led to the US Food and Dmg Act of 1906 which set up a certification procedure which ensured the identity of the colorant and the levels of impurities specifications for each food, dmg and cosmetic (FD C) color permitted for each colorant.4... 

Hoder et al. (1984) studied clonidine in seven newborn infants with neonatal narcotic abstinence syndrome and found no significant changes in blood pressure, pulse, or electrocardiograms (EKG) in any of the seven infants. One infant had a transient abnormal eye exam and two infants developed a transient mild metabolic acidosis. On follow up 4-9 months later, four infants were found to be developmentally age appropriate. However, Huisjes et al. (1986) reported that 22 children exposed in utero to clonidine as result of treatment for maternal hypertension had increased sleep disturbances and hyperactivity, compared to a control group at a mean age of 6 years. It is unclear whether these differences were a direct effect of clonidine on prenatal development. More sophisticated preclinical studies need to be done in this area. At best the level of short-term and long-term safety regarding clonidine is level C. 

Three levels of risk are suggested here (low, medium, and high) although some pharmaceutical and healthcare companies may like to consider five levels of risk to match the system integrity levels defined by lEC/ISO 61508 for safety critical systems. Each system should be rated against a number of weighted risk factors to determine an overall level of risk. Seven example risk factors are considered in Table 14.4 ... 

No specific occupational exposure limit has been established by Occupational Safety and Health Administration. Tolerance levels ranging from 0.1 to 0.5 ppm have been established for the presence of propachlor in seven crops. 

The Committee concluded that these seven flavouring agents, which are additions to the group evaluated previously, would not give rise to safety concerns at the currently estimated levels of intake. Six other substances proposed for evaluation in this group were not evaluated using the Procedure, as the Committee questioned whether they had flavouring properties. 

Step A3. With regard to those seven flavouring agents (Nos 1751-1757) evaluated via the A-side of the Procedure, the estimated daily per capita intakes are below the threshold of concern for the structural class (i.e. 540 pg/person per day for class II). According to the Procedure, there are no safety concerns for these seven flavouring agents when used at the currently estimated levels of intake. 

The essential objective of a conformity assessment procedure is to enable the authorities to ensure that products placed on the market conform to the requirements expressed in the directives and, these products must meet the high level of safety that the directives seek for a given product or product sector. There are seven modules in 93/465/EEC, and the generic directives (LVD, EMC, etc.) or product-specific directives (machinery, etc.) will set the range of choices that may be considered, as follows ... 

The Trends in risk level (RNNP) project administered by the Petroleum Safety Authorities (PSAN) use the common DSHAs in their questionnaires. In addition to the DSHA-set from RNNP/PSAN, we obtained seven sets of DSHAs during the interview study. Overall, the interviewees reported that the DSHA-sets were developed with reference to the traditional operational environment, and that lO had not been explicitly... 

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