Consultancy

Underwater noise can be created by a multitude of man made activities such as ship movements, construction adjacent to a river, through to the extreme levels of sound generated during the use of explosives underwater, for instance for decommissioning of unwanted oil and gas installations.

The noise from these activities has the capacity to directly cause disturbance to marine animals such as fish, seals, whales, dolphins and porpoises, and may also cause secondary effects for instance by disturbance of their food.

The effects of noise can include death or lethal injury, physical injuries that can have longer term consequences for the animal such as deafness, and sub-lethal behavioural effects such as the avoidance of an area. All of these may have significant consequences for individuals or stocks of a species.

Hence, it is generally a condition of consents issued for many activities that

1. the likely level of noise created by various activities is estimated prior to an operation being undertaken,
2. and that where the noise of an activity is sufficient to create an adverse effect, mitigation measures are introduced.

Subacoustech has developed proven strategies to model the likely level of noise, interpret it in a biologically significant way, estimate impact zones and measure the actual noise, during the activity, to ensure the levels are not exceeding predictions for which mitigation measures may have been put in place.

To see previous clients for whom we have performed these tasks, please click here.

Modelling of Underwater Noise and Vibration

Subacoustech has incorporated years of experience in underwater noise to develop a model to predict how a sound will propagate through a specific environment.

Estimation of Impact Zones

A critical part of measuring noise is being able to analyse the noise in a way that will assess the environmental effect of noise, so that the measurements can be interpreted and processed in a biologically significant way. This can then be used to estimate zones within which lethal, physical and auditory injury may occur for different species. Subacoustech is highly skilled at interpreting underwater noise measurements.

Measurements of Underwater Noise and Vibration

Subacoustech has the highest standards of underwater sound and vibration recording equipment in the world. The hydrophones are capable of measuring underwater sound at levels below sea state zero, or to the extreme levels encountered during underwater blasting.