Inaudible Low Frequency Noise & Vibration

Low frequency noise is increasingly becoming an problem in the industry and environment which is frequently not recognised and addressed in plant design. The problems are usually associated with vibrations felt in dwellings; and in this case at the world’s largest offshore gas platform Sarawak was felt in the Living Quarters.

We were requested to undertake a study to quantify the severity of the problem and to identify root causes upon which remedial solutions were developed. From the site surveys, it was apparent that noise measurements in dBA as conventionally used in normal measurements and assessment did not pick up the inaudible low frequency noise which instead required analysis in linear frequency weighting.

The root cause was successfully identified. The Study also involved noise modeling validated against measurements, upon which noise reduction options were examined and optimised using noise models before a final noise control design was selected.

“You got to help us solve this problem”

Viershon Nadarajah
Project Manager E11P‐B, Sarawak Shell Bhd

From left to right: Exhaust from the glycol re‐boiler identified as the root cause of a low frequency noise and vibration problem | View of the Gas Production facility, SSB E11P‐B, offshore Sarawak

From left to right: Exhaust from the glycol re‐boiler identified as the root cause of a low frequency noise and vibration problem | View of the Gas Production facility, SSB E11P‐B, offshore Sarawak



Noise maps in overall dBA (left) and dB Linear (right)

Noise maps in overall dBA (left) and dB Linear (right)