I thought I would share this information with the rest of the Power Plant community. I found this document on the web written by GE EH&S regarding the noise exposures to power plant employees. See link for full version. http://www.gepower.com/prod_serv/pro...ds/ger4239.pdf

Introduction
"Noise has become an increasingly important subject in the matter of workers’ protection and health. Hearing impairment has been identified as one of the major health issues for Power Plant Employees and Owners. Studies indicate that exposure-related hearing loss is caused by exposure to high noise levels over extended periods of time. Hearing loss is therefore associated with both the level and duration of the noise to which an individual is exposed. Exposure-related hearing loss can also be caused by exposure to extremely loud impulse type noises.

To address this concern, Health and Safety Agencies in many parts of the world have developed noise exposure limits for Power Plant Employees.Typically these Agencies have established lower (trigger) levels and upper average exposure limits, along with peak noise limitations. The lower level typically "triggers" specific actions, which must be taken by the Power Plant Owner. The lower (trigger) and upper exposure limit values are usually the average level of noise a worker is exposed to for an eight (8) hour time period. For the protection of Power Plant Employees, Power Plant Owners must take specific actions when the Employees’ exposure to noise has reached these levels. It should be noted that these regulations do not specify a limit on the noise level of equipment. The regulation is on the level of noise a Power Plant Employee may be exposed to, over a specific period of time.

In response to these requirements, Power Plant Owners are specifying lower limits for noise levels from the power generation equipment they are purchasing. In many cases, the noise levels that are specified by the Power Plant Owners are at or below the lower threshold for action established by the Health and Safety Agency, and/or are specified as maximum allowable levels.While ensuring that the respective limits will be met, these noise level requirements are typically more restrictive than required to comply with the specified exposure limits, and impose considerable unnecessary costs to the Power Plant Owners. The purpose of this paper is to discuss the intent of these requirements and explore the various methods that can be used to ensure the health and safety of the Employee, while controlling the cost impact on the Power Plant Owners."

Thanks for the Link..
It appears to be broken but maybe it will work later.

I recently participated in a Noise Measurement to determine outside noise level produced by a power plant with 2x MAN 18V48/60 with full load +auxiliary systems like radiators etc.

Measurements where taken along the fence which was some 15 to 20 m from the power House wich has a 4" panel cover and roof. We got less than 70 dB in most of the 12 points that we measured.

What I didn't understand is that, I am not a noise measurement expert, but the standard applicable to be used for the measurement was ISO 11690-3, but this one I got to know later is for measurements on inside working spaces like the Engine room or other not for outside measurements.

Is there another standard that could have been used for our measurement? or this one works? I am not familiarized with what this ISO states becasue I dont have acces to it but maybe it was applcable in our case.