Assessing noise risks for larger / more dynamic sites
You need to be able to properly assess or estimate noise levels for larger / more dynamic sites so that you can put in place appropriate controls. The Noise Regulations define 'exposure action values' – levels of noise exposure which, if exceeded, require you to take specific action. There are 'lower' and 'upper' action values.
- Lower exposure action value – daily or weekly personal noise exposure (LEP,d or LEP,w) of 80dB. As a general rule of thumb, the noise level is probably 80db or more if the noise is intrusive but normal conversation is possible between people 2 m apart - comparable to a busy street, a typical vacuum cleaner or a crowded restaurant.
- Upper exposure action value – daily or weekly personal noise exposure (LEP,d or LEP,w) of 85dB. As a general rule of thumb, the noise level is probably 85 dB or more if it is necessary to shout to talk to someone 2 m away, for more than about two hours per day in total.
- Peak sound pressure – these very loud 'impact noise' levels can be more damaging than the daily / weekly noise exposures and present a risk of immediate and permanent hearing loss. The lower and upper action values for these are 135 and 137 dB (LCpeak) respectively. Damage caused by them will be in addition to any damage resulting from the daily / weekly noise burden.
Where your employees are likely to be exposed at or above the upper exposure action value, you must take action to reduce noise exposure with a planned programme of noise control. Follow the control solutions listed accordingly. Some tasks with indicative noise levels at or above the upper exposure action value are given below. Actual levels can vary (possibly significantly) from this depending on what you are doing and where you are doing it. The specific equipment and how well it is maintained / used can have a particularly big impact.
| Task | Average Noise level (LEP,d) |
|---|---|
| Carpentry | 92 |
Concrete
|
85+ 85 85+ 89 |
| Driving a dumper or roller | 85+ |
| Formwork | 92 |
Labouring:
|
97 100 94 91 90 – 110 |
| M&E general installation | 89 |
Piling:
|
85+ 100+ |
| Reinforcement work | 86 |
The noise exposure calculator and ready reckoner can also help you work out your daily noise exposure, weekly noise exposures, and estimate the performance of hearing protection. Use manufacturers' noise data but check it is relevant to the work you are doing. Detailed historic noise level data for a range of general site activities is contained within the BSI standard (BS 5228-1:2009 – Code of practice for noise and vibration control on construction and open sites). Further information on assessing noise exposures. Seek specialist help if you are unsure.