Research by the Health and Safety Laboratory (report RR720) shows that the common assumption that PPE is a reliable “solution” to hearing damage risk problems is simply untrue, leaving many personnel still at risk and many companies open to claims. Some of the key findings of the research are:-
The inadequacy of PPE performance in many real-world situations is also born out by the continuing tidal wave of hearing damage claims (£400 million in one year (2014), despite (or even because of) the over-reliance on PPE without understanding the performance limitations away from the lab. This also brings into sharp focus the need to reduce noise levels to reduce risk, even when the levels cannot be reduced to below 85dB(A).
As a rule of thumb, provided effective (and time-consuming) management systems are in place, most good quality PPE can be made to work up to noise levels of around 95dB(A). Above this level, it becomes increasingly difficult to guarantee sufficient protection and above c 100dB(A) it becomes virtually impossible. However, if you can use very low-cost engineering noise control measures to cut the noise, the risk can be reduced dramatically so that PPE works. For example, reducing noise by 3dB from 97dB(A) down to 94dB(A) halves the risk (and PPE is more effective). By 6dB and the risk falls by 75%.
There is more on the topic of self-financing noise control, including a White paper here.