On risk and risk analysis

Increase in demand for standby power sources and disruption in power supply has increased the use of generators manifold for domestic and industrial consumers leading to objections on their use concerning noise pollution. The work presented here aims to focus on how generator set noise is propagated, controlled and reduced to a limit as defined by domestic laws. The presented work is in fact a feasibility of a simple and effective design of an acoustic enclosure for portable generators aims at reducing the radiated noise. This effort is a multi-disciplinary work that comprises acoustics, heat transfer and material science. Heat generation and requirement of cooling air leads to a heat transfer model with internal forced convection. The design is a balance of noise control and thermal management. Noise generating areas have been identified and conventional passive noise control techniques have been used to control and reduce the noise. Acoustic barriers and insulation are used to control the noise propagation at its transmission path. In the conclusion comparison and results of noise are plotted using sound measuring techniques and devices as well as the thermal profiles of cylinder head are compared with and without canopy.

https://eujournal.org/index.php/esj/article/download/2509/2382

Design and development of noise suppression system for domestic generators

On their way to social acceptance, many technologies experience periods of public concern, controversy, and social opposition. Sometimes these responses to technologies are short episodes, motivated by naive fears or esoteric values of a small segment of the public. As in the case of religious opposition to the implementation of lightning rods (see Mazur, 1981) these episodes may be a little more than amusing footnotes in the history of an ultimately successful technology. In other cases, the public responses may swell to a strong social movement against the technology that leads to its disruption, halting, or eventual abandonment. Water fluoridation, nuclear power, and the SST are recent examples of technologies suffering this fate (see Lawless. 1977; Mazur. 1981; Nelkin, 1979).

Public Disputes about Risky Technologies Stakeholders and Arenas

This paper analyzes the noise pollution problem of high-speed trains (Shinkansens) in Japan. A decision analytic approach is used to structure the problem and to identify sources of conflict among the actors involved in railway noise standard setting. The Shinkansen noise pollution problem is characterized by the inherent inequity of the risk-benefit distribution resulting from the train operations. While the benefits of high-speed transportation are shared by many travellers, the burden of the noise impact is carried by relatively few residents. This conflict is institutionally expressed in the opposing values of the Japanese National Railway and the Nagoya Association against Shinkansen Pollution. In attempting to resolve the conflict, the Environment Agency of Japan set noise pollution standards of 70-75 dB(A). The Japanese National Railway argued for less stringent standards because of economic, speed, and service objectives. Resident organizations, in contrast, requested more stringent standards because of psychological and health impacts. However, both arguments appear to have influenced the final standard only indirectly. Instead, standards were set mainly on the basis of noise-complaint relationships and on the basis of consistency with existing noise standards.

S. Ikeda

Papers

Standards against noise pollution: the case of Shinkansen trains in Japan