Workplace Noise Assessment January 2005 Think Environment Think Casella

Do We Need a Survey? Can you understand normal speech at 2 m? (1 m for old regs) Has your noise survey meter indicated noise levels are above the first action level? Does your company have a policy of regular noise surveys? Think Environment Think Casella

Who Should Carry Out the Survey? A competent person Think Environment Think Casella

What is a Competent Person The person should have the following knowledge and experience Purpose of assessment Understanding of what information to be obtained Appreciation of their own limitations How to take measurements How to record, analyse and explain the results Care of noise measurement equipment Think Environment Think Casella

Where Do You Start? Tour of the factory Make notes about noisy machines Ask workers about their work patterns Are there any machines that are not working Determine shift patterns Assess the risk Think Environment Think Casella

Choice of Noise Equipment Do we need an integrating SLM? Do we need to carry out octave band analysis? Will “C” weighting be required Do we need to measure “peak”? Do we need dose meters? Think Environment Think Casella

Calibration All noise measuring instrumentation must be calibrated before measurements take place Equipment should be calibrated after use Think Environment Think Casella

The Survey Where to measure Close to operators ear Not too close to affect measurements Should a tripod be used? SLM should be held at arms length Think Environment Think Casella

The Survey How long? How long should measurements be? Long enough to be representative Measure a complete cycle of machine Do I need to use a dose meter? Are there workers that are transient? Think Environment Think Casella

The Survey Observations How is the noise generated Does the noise have peculiar characteristics Could screening be used to reduce noise Could machines be moved Think Environment Think Casella

The Report Introduction Methodology Results Discussion Recommendations Think Environment Think Casella

Introduction Sets the scene Details of where the survey was made The shift patterns Who carried out the survey Think Environment Think Casella

Methodology State the methods used The equipment used in survey Serial number of instruments Calibration Methods used Think Environment Think Casella

Results Results & Calculations All the raw data from the survey Calculations of LEP,d’s Factual data about machines Calculation for hearing protection Think Environment Think Casella

Discussions Talks about the survey in depth Contain factual information on survey Point out areas where action levels are exceeded State areas where signs are to be erected How to silence noisy machines Ear protectors Think Environment Think Casella

Recommendations Review the items contained in discussion Final recommendation on how to control noise Recommend ear protection to be provided Training to be given When survey should be repeated Think Environment Think Casella

Case Studies Noise at Work Think Environment Think Casella

Case 1 Manufacturer of electrical switchgear Various metal work processes About 200 employees Peak levels of 140 dB exceeded due to poor handling of metal sheet Think Environment Think Casella

Case 1 Hand held sound level meter measurements Personal dose meters LAeq Octave bands Personal dose meters 12 members of staff Think Environment Think Casella

Case 1 Less than 80 dB(A) Bending machine Deburring machine with silencer Press Think Environment Think Casella

Case 1 80 to 85 dB(A) Assembly area Hole punch Shot blaster Think Environment Think Casella

Case 1 85 to 90 dB(A) Laser cutter Hand deburring Think Environment Think Casella

Case 1 90 + dB(A) Circular saw Cross cut saw Pneumatic riveting Circular sander Frame riveting Think Environment Think Casella

Case 1 Material handling 2 saws - very high noise levels staff training 2 saws - very high noise levels Hearing protection zone (even though intermittent use) Think Environment Think Casella

Case 1 Laser cutter Belt sander for deburring inherently quiet but noise from material handling - shaking out Belt sander for deburring Hearing protection zone Think Environment Think Casella

Case 1 Shot blaster Hand deburring machine fit attenuator to exhaust 86.5 dB(A) in use - 77.6 dB(A) with manufacturer’s silencer Think Environment Think Casella

Case 1 Factory ventilation fans remove individual controls reduce maximum speed Think Environment Think Casella

Case 1 Ear plugs were already widely used and proved suitable for all situations Recommended workers in dirty areas should use ear defenders Think Environment Think Casella

Case 2 Significant variation of noise levels Workforce static Approx. 85 employees in the workforce 7 measurement sessions 6 dose meters Think Environment Think Casella

Case 2 Result summary for worst affected LEP,d Lpeak 1 90 130 2 85 130 1 90 130 2 85 130 3 87 135 4 81 126 Think Environment Think Casella

Think Environment Think Casella

Case 2 Result summary for worst affected LEP,d Lpeak Trumpet 90 130 Viola 85 130 Cello 87 135 Percussion 81 126 Think Environment Think Casella

Think Environment Think Casella

Case 2 Small curved clear plastic screens Ear plugs Dose reduced by 1-3 dB(A) Lpeak reduced by 4-5 dB Ear plugs with flat attenuation properties Think Environment Think Casella