The diving area noise analysis is related to tree main factors:
1. Vessel Background noise
2. Vessel related equipment noise figure
3. Diving Equipment noise figure
The vessel designer and the shipyard are normally prepared to execute the noise analysis in each vessel compartment, to verify compliance with the applicable rules and regulations.
At this respect the scope of work of Drass is to provide the noise figure of the diving equipment.
These data are generally available in Drass interface drawings.
In general Drass has not the information and the tools to execute such analysis for the entire compartments which are dedicated to the diving equipment.
In fact such compartments contain vessel related equipment and are subject to the vessel background noise which are both unknown to Drass.
Moreover the simulation of the noise figure in the compartment is executed with specific software generally available to the vessel designer and to the shipbuilder.
During the commissioning phase, the compliance of the noise values with the reference Rules is verified by means of direct measurement of the effective noise levels. To support the shipyard and the vessel designer Drass is available to verify in the early stage of the design, the results of the noise analysis together with vessel designer or with the shipyard, in order to identify the eventual corrective actions.
In addition Drass is responsible for the compliance of the effective noise figures with the design parameters, when the noise levels are measured on board.
Drass equipment is designed and built to be in compliance with the admissible noise level, conditioned to the correct positioning in the general arrangement and to an acceptable background noise level and vessel related equipment noise level.