Workplace specific assessments

In the case of significant accidental exposures, it will often be necessary to use parameter values in the calculation of tissue or organ equivalent doses and effective dose that ate specific to the conditions of exposure and to the individual. Similarly, in routine situations it may be necessary to take account of the particular circumstances of exposure rather than using default parameters. The new model for the respiratory tract [34] adopts an AMAD of 5 pm as a default particle size when no specific information is available. Regional deposition of airborne particles is subject to the mechanisms of sedimentation, impaction and diffusion. Deposition throughout the respiratory system and hence inhalation dose coefficients depend upon aerosol parameters, such as the AMAD. Similarly, ingestion dose coefficients depend upon the choice of an appropriate/j value. 

Influence of AMAD on the committed effective dose from inhaled as type M or type S compounds [40]. 

Direct or indirect measurements provide information about the amount(s) of radionuclides present in the body, in parts of the body such as specific organs or tissues, in a biological sample or in a sample from the working enviromnent. The first use of these data is likely to be an estimation of the intake of the radionuclide by the worker. Biokinetic models which describe body and organ contents, and activity in excreta, as a function of time following intake, and exposure models which relate intake to workplace conditions, are used for this purpose. Alternatively, measurements of activity in the body can be used to estimate dose rates directly. The calculation of committed doses from direct measurements still involves the assumption of a biokinetic model if sufficient measurements are not available to determine retention functions. 

The ICRP has pnblished generic valnes of m t) for selected radionuclides in tissnes or excreta, together with retention functions for systemic activity [8]. Further information is provided in ICRP Pnblication 78 [9] using more recent biokinetic models. 

When significant intakes may have occurred, more refined calculations based on individual specific parameters (special dosimetry) should be made (Section 3). If multiple measurements are available, a single best estimate of intake may be obtained, for example, by the method of least squares [41, 42]. 

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Derived from task analysis or work study, job safety analysis, whether effected as part of work study or not, can do much to eliminate the hazards of a job. The analysis identifies every single operation in a job, examines the specific hazards and indicates remedial measures necessary. It involves the examination of a number of areas, including permit to work systems, influences on behaviour, the operator training required and the degree of supervision and control necessary. Job safety analysis can feature as part of a workplace risk assessment. 

The legislation related to occupational health and safety defines ways to minimize risks. However, the legislation is not able to cover all the specifics of different workplaces. It is thus the duty of management staff to identify what may be hazardous to employees at a workplace, to assess the frequency and potential consequences of the hazards, and eventually, adopt measures to reduce the risk. 

Apply to all workplaces, unless specifically excepted, and require a fire risk assessment where necessary, appropriate fire-fighting equipment with detectors and alarms measures for fire-fighting emergency routes and exits maintenance of equipment provided. 

Passive dosimetry, which proved useful for the pursuit of better workplace hygiene in agriculture during the past 40 years (Durham and Wolfe, 1962), yields unvalidated and excessive amounts of worker exposure (Krieger, 1996). Currently, our approach with respect to indoor and agricultural exposure assessments has been the evaluation of exposure estimates using well-known, studied chemicals to first understand the work task and at a later time develop chemical-specific studies as required in the regulatory arena. 

Special process and product specifications have been set forth for companies in the chemical industry. Additionally, specific limits must be observed for pollutant or VOC (volatile organic compounds) emissions. Specific maximum allowable concentrations at workplaces must not be exceeded. Both the transport of chemicals and the recycling or disposal of chemical wastes are subject to particular requirements. Periodic hazard assessments - which in Germany, for example, are mandatory according to the Ordinance on Industrial Safety and Health (Betriebssicherheitsverordnung, BetrSichV) - are a must requirement in the chemical industry. To achieve a Continuous Improvement Process, product and process requirements must be identified, evaluated and monitored on a regular basis. 

Before completion of an EU risk assessment on TCE, Sweden decided that epidemiological evidence on the hazardous properties of the chemical was sufficient to warrant strict regulatory control in the workplace (through the application of Article 138 of the EC Treaty). Sweden therefore began to implement a company use-specific authorisation system. Sweden s action was later challenged by the European Commission as causing unnecessary barriers to trade, but a European Court of Justice ruling upheld the Swedish system. 

As a supplement to R2.2.1766-03, specific recommendations are planned on methods and criteria assessment (scales, models, etc) of workers health (morbidity, mortality, etc), workplace factors (noise, vibration, dust, chemicals, etc), work load (physical load nervous tension), and reproductive health risk assessment. Relevant data have been published in handbook on occupational risk (Izmerov Denisov, 2003). 

The results obtained categorically confirm the adequate choice of biomarkers for assessment of internal exposure. The determination of specific metabolites of carbon disulfide in urine can be widely applied, as the methods are specific and non-invasive. As mentioned above the only source of TTCA appearance is the inhaled carbon disulfide. It should be underlined that the high correlation between external and internal exposure proves the credibility of the used sampling strategy and implemented GC methods for determination of carbon disulfide concentrations in workplace... 

These regulations were made undo- the authority of the Health and Safety at Work etc. Act 1974, and came into force from October 1989. They set up a basic framework allowing the United Kingdom to comply with EC health and safety directives. COSHH requires employers to assess risks from hazardous substances used in the workplace. A written risk assessment is required which is specific to each workplace this written assessment must be available to employees. These assessments are subject to examination by Health and Safety Executive inspectors. 

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