Stress and Dynamic Under the Pressure of Vibrations - Assignment Example

Stress and Dynamic Stress and Dynamic What is the scope of BS EN 14253:2003+A1? Avoiding vibration is a difficult task. Vibration happens due to manufacturing tolerances, rolling and rubbing, and contact between machines among other factors. Vibration results to wear, tear, and stress to machines. On the other hand, vibration has negative impact on the health of human beings. Both forms of vibration; whole-body vibration (WBV) and hand vibration pose some danger to those getting exposed to them. A strategy incorporating the European Standard provides a realistic idea of the daily exposure to vibrations of a subject as well as the important uncertainties. This process of evaluation is done procedurally by identifying the type of operation in question, selecting the operations requiring evaluation, determining the r.m.s per operation, and establishing the daily vibration exposure. 2. Normative references in the document The date’s references apply the cited edition. The undated references apply to the current edition with amended documents. The normative references available are; Instrument and the response of human beings to being. These are ISO 8041:2005 and EN ISO 8041 respectively Evaluation of vehicle vibration in respect to EN 30326-1 Part I of the general requirements of mechanical and shock vibration, ISO 2631-1 Calibration methods outline for all parts as stated in ISO 5347 Mechanical vibration and shock as stated in ISO 5348 and All parts generalizing on the methods of calibration, ISO 16063. 3. Evaluation of quantities for exposed vibration Since WBV and HV have become sources of exposure to vibration, it is necessary that the two principles used for evaluation be used. The two principles are; frequency-weighted acceleration and the duration absorbed by the body on a daily basis. The two principles are measured in m/s² and Ti respectively. The Root Mean Square is also applied to the former principle. However, the Vibration Dose Value (VDV) need to be considered as outlined in the Physical Agents 2002/44/EC document. 4. Exposure Profile Exposure profile is similar to risk assessment of vibration exposure. The set out guidelines used ensure that the units of exposure are within the required vale in an 8hour period. Exposure profile is an important issue that focuses on the measurements done and how they contribute to vibration exposure on a daily platform. The operations are identified with consideration to the following: The type of equipment the employee uses The working conditions The type and nature of ground the employee works in and on Operation done by the employee locally The time frame of the operation The rate at which the operation is done The current state of the operation to be carried out and The seat provided (Ignacio & et al, 2006). 5. Organization of the measurements The manner in which an employee gets exposed to vibration depicts the willingness of the employee to get monitored. However, it is important that the employer looks at modest ways of organizing and measuring vibration. Plant operators in a road construction firm get exposed to vibration form the machines such as graders, roller compactors, dump trucks, and tractors. The mode of vibration in this context is whole body vibration. Measurement, evaluation, and analysis of exposure to vibration are best done annually. Steps towards measurement of vibration The selection process where 30 plant operators are chosen. The plant operators need to be exposed under similar working conditions and plant machines. The duration of exposure on daily basis ought to be checked and confirmed Take the frequency weighted vibration acceleration and report it in m/s² according to Manfield (2004). 6. What shall the duration and number of vibration measurement be? The data collected is analysed on a monthly basis per individual. According to the measurements done, most plant operators were exposed to high levels of vibration during the dry season. This is so because most operations of the plant machines were made during this particular period. It also implies that the more an employee takes when exposed to vibration, the higher the doses the person absorbs. The values obtained are calculated to establish the 8-hour exposure. The dosage ranged between 0.35-0.56m/s². This implies that the dosage received is still within the required dose. 7. Equipment selection The vibration parameters determine the type of equipment to be used since each parameter uses different SI units. Vibration frequency unit measures vibration in Hertz while the velocity unit uses the rate factor. The displacement unit parameter uses millimetres to depict the intensity of movement from the point of origin and is denoted by D. These vibration parameters determine the type of equipment to be used. In this case, accelerometers are used to measure the intensity of vibration. Accelerometers are the preferred equipment used to measure vibration. Their choice is defined by the magnitude of vibration, the range of frequency, the type of surface in used, and the working environment. The magnitude of vibration requires that the dynamic range accommodates gravitational factors as well as vibration. Accelerometers are very sensitive to temperature and humidity. This implies that environmental factors must be considered as outlined in the normative reference EN ISO 8041. 8. Verification of measurement equipment This is an important process that ensures that the system functions within the desired tolerance. This is outlined in the normative reference EN ISO 8041. ISO 5347 and ISO 16063 require that the transducers are checked. This is a routine practice ought to be done annually and even after rough handling. 9. Uncertainty in vibration measurements There are several factors that affect uncertainty of measurement. These factors are related to individual measurements like accuracy of the instrument used, calibration, electrical interferences, challenges on mounting the accelerometers, orientation of the accelerometers, and changes effected by the methods of the operator. There are also changes that happen in the course of the day such as the condition of the machines and characteristics of the travelling surface. Furthermore, the nature of operation also shapes the sources of uncertainty. Uncertainty in the context of exposure duration is affected by; The measured period of work cycles Estimates of the work cycles on daily basis The time of exposure according to the operator and The varying of the daily tasks. 10. Describe the advantages of having read the BS EN 14253:2003, +A1:2007. Reading the document offers several advantages. These are; Exposure to vibration pose various dangers to the health of operators The European standards set a guideline on how to measure exposure to vibration The VDV required so that an operator can control exposure to harmful vibration The modes of measurements, instrument in use, as well as the uncertainties and errors that may lead to inaccurate information. Bibliography Finucane, E. W., 2006. definitions, Conversions, and Calculations for Occupational Safety and Health Professionals. 3rd ed. London: CRC Press. Ignacio, J. E. & et al, 2006. A Strategy for Assessing and Managing Occupational Exposure. New York: AIHA. Manfield, N. J., 2004. Human Response to Vibration. London: CRC Press. Read More