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Here are five steps that businesses can take to ASSESS and CONTROL excessive noise levels:

1. Establish if there are any noise generating processes in the workplace by conducting a preliminary assessment of all working practices.

• You may wish to carry out a basic noise measurements using a suitably calibrated sound level metre.

2. Once the areas that pose a potential risk have been identified, it’s very important to recognise which employees could be at risk and evaluate how the harm may occur.

• For example, deafness, damage to hearing or impaired communication.
• It’s also important to consider susceptible employees and those that may already have a hearing impairment. 

3. Once usual work routines have been determined, individual noise measurements can be carried out to assess the typical exposures and look at those potentially at risk. There are two ways to conduct these:

a. The first method is to use an integrated sound level metre to determine representative A-weighted average noise level readings – taken from each task undertaken by employees.

• The individual exposure levels can then be accurately determined.
• This type of equipment uses an A-frequency filter which effectively replicates the response of a human hear to noise. This ensures the level of risk can be assessed, as opposed to the noise level.

b. The second type of monitoring involves using a dose metre which can be worn by an employee for an entire shift, no matter if the employee is constantly on the go, or needed to fit in tight spaces – location and work patterns are not issues.

• Another essential measurement to make is the C-weighted peak measurement. This assesses the risk associated with peak noise like sudden crashes, bangs or loud alarms starting.
• Once all the measurements have been taken, a noise control action plan needs to be created. This will demonstrate the various steps needed to be taken to control and identify any risks.

• The plan should include a list of prioritised actions which solve immediate risks and consider the general duties to reduce noise levels in the workplace.
• Provisions should be made for suitable hearing protection where noise levels cannot be combatted by other means.
• Arrangements should also be made to provide training to the entire workforce in respect of risks and actions and how to minimise noise levels.

4. A report should be compiled providing evidence of the decisions made to comply with the law. It should include:

• Evidence of a noise survey
• Identification of the noise hazard areas
• Details of warning sign placement
• Prescription of suitable PPE
• Details of training programmes
• Quiet purchasing policies
• Health surveillance records
• Measures to control noise without the reliance of hearing protection

5. The noise control programme in the workplace should be reviewed regularly to consider new equipment, employee working patterns and any changes to the building layout(s).

• Organisations with staff receiving exposures of the upper levels as defined by the HSE, should have a health surveillance programme that highlights any deterioration in their hearing due to inaccuracies in the noise control programme.

Guidance On Selecting Hearing Protection

To choose the best type of hearing protection for your business, noise risk assessment results along with information from the PPE supplier need to be carefully followed. The main types of hearing protection are as follows:

Ear plugs

Ear plugs are inserted into the ear canals to protect them from exposure to high levels of noise. There are many types of ear plugs. Usually, they’re made from soft plastic, polyurethane, silicone or PVC. When fitted correctly, they’re comfortable and are an effective way of providing good sound attenuation.

Ear Muffs

Ear Muffs normally provide less protection than ear plugs, because they only sit over ears, rather than directly in the ear canal. They are very easy to fit, but they can become uncomfortable in hot environments.

Canal caps/semi-insert ear plugs

Both canal caps and semi-insert earplugs are convenient for jobs where the worker must frequently take their hearing protection on and off. Canal caps have rounded heads that cover the entrance to the ear canal. On the other hand, semi-insert ear plugs usually have conical tips that can be pushed into the ear canal.

Whichever type of hearing protection you choose, the most important factor is the level of noise reduction they provide when compared against the measured daily average exposure. Hearing protection will have a ‘dB’, or decibel rating – this indicates how much the noise is reduced. The overall aim should be to reduce noise levels at the ear to between 70 – 75 dB.

If ears are over-protected it can create additional safety issues, such as difficulties with communication and the inability to hear warning signals. Workers may become isolated from their environment, causing them to remove their hearing protection - which could lead to hearing damage.

Ototoxic Chemicals

Ototoxic chemicals are a collection of compounds that can adversely affect some parts of the ear, regardless of exposure to noise. However, when ototoxic exposure is combined with noise exposure, the combined effect may be additive or even synergistic. Ototoxic chemicals can contribute to sensorineural hearing loss, which is often permanent due to the adverse negative effects on the auditory nerve and inner ear hair cells and the limited ability of these cells to repair themselves effectively.

Approximately 750 chemicals are thought to be ototoxic, but research is still in progress, some common examples are solvents such as toluene, styrene and xylene and metals such as lead, tin, cadmium and mercury.

Those working in industries that utilise ototoxic chemicals in combination with loud machinery are at a higher risk of potential severe hearing loss. It is important to identify individuals and processes that may involve both forms of exposure and ensure adequate controls are in place to prevent long term hearing loss.

For more information on chemical exposure monitoring click here