Identifying noise hazards is the first step and need not require specialist skills, but it must be done in consultation with workers and their health and safety representatives; as a guide, needing to raise your voice to someone a metre away means the noise is probably hazardous. Hazards arise from the physical and psychosocial environment, the equipment, materials and substances used, the tasks and how they are done, and work design and management, and exposure is cumulative across noisy activities. Hazards are found by walking through the workplace, observing work and plant in use, talking to workers about how work is done and their problems, inspecting plant, consulting manufacturers, suppliers, industry associations and specialists, and reviewing incident and monitoring reports; the Appendix C checklist supports the process. Regular walk-arounds reveal where noise comes from and which tasks or processes contribute, including vibration and ototoxic exposures, and obvious sources such as rattling panels should be fixed immediately. Noise emission information should be obtained from designers, manufacturers, importers and suppliers, who have a duty to provide it, and regulators, associations, unions and consultants can advise; workers compensation claims for hearing loss and findings from repeat audiometric tests should be checked, since hearing loss attributed to a task signals a hazard for others. In consultation, the PCBU makes a list of all noisy activities that may pose a risk; a yes to any checklist question suggests hazardous noise, and where the level of exposure or how to control it is unclear the next step is to assess the risk.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.