Introduction: A noise expert, Industrial Noise and Vibration Centre, approached National Grid with a novel vent silencer design that requires further development. This is potentially a low cost, simple alternative, much more suited to a range of applications on the National Transmission System (NTS), in comparison to off the shelf solutions.

With the noise implications of National Grid’s venting operations becoming more highly scrutinized, resulting benefits of this project would include:

• Reduction in noise levels – for all venting activity on a national basis. It is expected that such a device may take at least 20 dBA off the current noise level.

• Deduction in affected/notification zones for venting. This novel approach, in controlling the rate of gas/air mixing, has the potential to impact on the assumptions made as part of a risk assessment and the determination of hazardous areas.

• Reduction in health and safety issues for operatives – exposure times and noise levels.

• Possible reduction in operations timing – greater flows for similar noise outputs.

  The proposed solution would therefore enable National Grid to reduce the impact of its operations on the environment and on customers and stakeholders in vicinity of gas transmission assets.

Objectives:

The intention is to carry out the required research, development and testing of a proposed high pressure
venting silencer with the Industrial Noise and Vibration Centre. The silencer has the potential to deliver
reduced noise levels, reduced health and safety exposure and also improve public perception and reduce noise
pollution during these necessary venting operations.

Expected Benefits: To deliver a new design of vent silencer suitable for use at national transmission system (NTS) compressor sites and NTS pressure reduction installations (PRIs).