Control measures existing, evaluation

During the evaluation phase, the various types of existing control measures and their effectiveness are also studied. Control techniques are presented in more detail in section 3-4. During the evaluation study, the likelihood of large and small leaks must be considered. 

In the EU, the current chemical control measures, based on a network of legislation for hazard communication and safety assessment, are soon to be dramatically revised. To set the scene for this forthcoming fundamental change to chemical control in the EU, the key facets of the existing measures are described briefly i.e., notification of new chemical substances, the relatively-limited measures to evaluate existing substances and hazard communication. There have been problems with the current scheme, principally the disparity between the safety data on new and existing substances. 

After assessing the hazards and risk, the next job is to assess the existing safety/control measures or barriers in place. Obviously, this is done to evaluate the adequacy of control measures to prevent or mitigate major hazardous events. There are a number of ways and means to achieve this (see Chapter II). From experience, one way is to... 

It is a creative brainstorming approach where a group of experienced people pose questions or voice concerns over a process and operational aspects of a system hinging around safety. An experienced review team can discern major issues pertinent to the organization of a process system. It evaluates existing safety issues and comes up with additional control measures. 

Safeguard Existing safeguard is evaluated during meeting and new control measure if any is prescribed. 

The process of identifying hazards and evaluating the level of risk (including to whom and how many are affected) arising from the hazards, taking into account any existing risk control measures. 

Evaluating existing control measures (workplace precautions and risk control systems)... 

While measurements of results are common and an important part of any successful safety and health program, to be proactive and preventive you must consider different measurements such as effort being put forth to prevent accidents. These types of measurements are called measurements of effort and assess the amount of control that exists within the system. Measurements of effort evaluate ... 

After a MPC control system is installed, it is first evaluated in a prediction mode. Model predictions are compared with measurements, but the process continues to be controlled by the existing control system (e.g., DCS). After the output predictions are judged to be satisfactory, the calculated MPC control moves are evaluated to see if they are reasonable. Finally, the MPC software is evaluated during closed-loop... 

Odors are measured by their intensity. The threshold value of one odor to another, however, can vary greatly. Detection threshold is the minimum physical intensity necessary for detection by a subject where the person is not required to identify the stimulus, but just detect the existence of the stimulus. Accordingly, threshold deterrninations are used to evaluate the effectiveness of different treatments and to estabflsh the level of odor control necessary to make a product acceptable (8). Concentration can also produce different odors for the same matenal. For example, indole (qv) in low concentrations has the smell of jasmine and a low threshold of perception. In high concentrations, it has a strong odor of feces and CX-naphthyl amine as well as a considerably higher threshold of perception. 

In this paper I have tried to show that measurement of health benefits attributable to TSCA is not feasible. I hope that in doing so I have not belabored the obvious. For new chemicals and for most existing chemicals, prospective evaluation of health benefits to be achieved by various exposure controls will have to be based on extrapolation from microbial and animal data. However, while such extrapolation may be useful in a qualitative sense, quantitative risk assessment techniques involve considerable uncertainty, and in any case have not been developed for chronic effects other than cancer. 

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