WorleyParsons was engaged by Vale Inco Nouvelle-Calédonie to investigate the optimal positioning and heights of four evacuation sirens within the processing plant of the Goro Nickel Project. Consideration was given to achieving the ISO 7731 requirements of sound pressure levels.
The analysis incorporated existing machinery noise provided by an external assessment, plant layout and the existing electrical infrastructure.
A sound analysis of three Klaxon ES-3 danger warning evacuation sirens located within a processing facility was conducted using SoundPLAN computer software.
The SoundPLAN model was used to generate a horizontal sound propagation contour map which allowed the coverage area of the evacuation sirens to be compared with the required coverage area.
The SoundPLAN model was further used to identify regions within the required coverage area which were not predicted to meet the following ISO 7731 design criteria:
- Sound pressure level must exceed ambient noise by 15 dB(A) or more;
- Sound pressure level must exceed 65 dB(A) at all times; and
- Maximum signal noise level should not exceed 118 dB(A).
Although the final installation locations of the sirens were primarily dictated by the existing electrical routing, some work was conducted to establish the optimal install locations and installation heights of the sirens so that the sound pressure levels throughout the coverage area were optimized.