How to compare machinery noise claims
Compare the same noise measure under matching operating conditions, with the test method and uncertainty stated. Agree representative factory runs, an installed-site check and remedies before ordering. For coordination with Chinese factories through its own staff in China, speak to Cambridge China Bridge.
Give suppliers the same comparison brief
HSE's buying guidance recommends asking suppliers the same questions so their answers can be compared. Send each supplier your material, intended output, operating modes, operator positions and proposed installation. Request separate information for standard test conditions and your intended use. A claim such as 'quiet running' is not a comparison basis.
The machinery sourcing guide covers the broader purchase and documentation checks. This guide adds a noise comparison and acceptance brief. Record the required throughput alongside the noise target so a supplier cannot demonstrate quiet operation by slowing the machine below your production needs.
Compare matching measures and configurations
Ask whether each claim describes workstation emission sound pressure, sound power or peak noise. Keep these in separate comparison columns. Request the units, weighting, measurement positions, test method, operating conditions and associated uncertainty. Ask for the underlying report and identify the machine, tooling, enclosure, silencer and extraction configuration tested.
Do not rank machines by the headline value until those details match. Mark missing or incompatible evidence as unresolved. Ask an acoustic specialist to review close comparisons and agree how uncertainty affects acceptance. Use test report verification to check that the evidence belongs to the offered model.
Agree representative factory runs before ordering
Add a noise schedule to the factory acceptance test. Include normal production and the noisiest intended tasks, using your material or an agreed representative substitute. Define load, speed, tooling, feed, extraction and enclosure condition. Include noisy parts of the cycle rather than allowing an idle demonstration to represent production.
Name the person responsible for measurement and agree suitable instruments, calibration records, measurement positions and background-noise handling. Require results for each agreed operating mode, with photographs of the setup and records of deviations. Video can document the run, but its recorded sound should not determine acceptance.
Check the installed machine in its working setting
Plan the site acceptance test before shipment. Check the delivered enclosure, silencers, mountings, extraction and operating settings against the factory record. Repeat agreed tasks after commissioning and record room layout, nearby machinery, background noise and operator positions. Separate a repeatable machine-emission check from a workplace operating check.
A factory noise result does not establish employees' exposure after installation. Assess actual tasks, time spent nearby and other noise sources with competent noise advice. Agree who investigates a mismatch and how machine changes, mounting, room conditions or neighbouring equipment will be distinguished before deciding the remedy.
Working out your own order? Send us the product on WhatsApp and we reply the same working day: WhatsApp us
Write acceptance and correction into the order
For each noise target, state the measure, configuration, operating task, measurement method and treatment of uncertainty. Keep factory and installed-site acceptance criteria separate. Obtain the supplier's written agreement, identify who witnesses each check and state which evidence the buyer needs before shipment release and final acceptance.
Agree who supplies corrective work, who pays for investigation and retesting, and what happens if the repeat check still fails. Record buyer approval for any changed configuration or accepted deviation. Request installation, operating and maintenance instructions for the noise controls, and keep the comparison records for future purchases.
Frequently asked questions
Can I compare machinery sound power and sound pressure?
Keep them separate. Ask each supplier for the same measure, test method, operating task and configuration before ranking machines.
Is an idle factory noise test enough?
An idle run does not represent loaded production. Agree runs using representative material, required throughput and the noisiest intended tasks.
Does passing the factory noise test prove the site is safe?
Factory acceptance does not establish workplace exposure. Check the installed machine and assess actual work patterns, room conditions and other noise sources.
What should I agree if machinery fails a noise check?
Agree investigation, corrective work, retesting, responsibility for costs and the buyer's release decision before ordering. Record any accepted deviation in writing.