Noise and the Work Environment: Are the Machines Loud? Are There Noise Regulations?
Where Noise in Food Plants Comes From
Food plants generally seem quieter than metalworking shops, but once the production line starts up, it's actually quite loud: motors on mixers and meat grinders, air compressors, refrigeration units, vacuum pumps, conveyor rollers, exhaust from pneumatic components, and metal trays and carts banging together. A single machine may be fine, but with several running at once in a space of tile and stainless steel that reflects sound, the overall noise adds up.
Are the Machines Loud?
It depends on the model and the site. Noise levels relate to the machine's construction, motor size, speed, installation method, and maintenance condition; the same machine sounds different mounted on a concrete floor versus a steel frame. Noise values for Dong-Yih models aren't listed in the specifications on our website; if you need them, please call 06-257-4644, or come to our factory to see the machines and hear them for yourself.
If a plant needs to assess noise, the most accurate way is to measure the sound pressure level at work positions under actual production conditions, using a sound level meter or personal noise dosimeter.
Are There Noise Regulations?
Yes. Article 300 of the Occupational Safety and Health Facilities Regulations (職業安全衛生設施規則; current text last amended June 30, 2026) sets the following for employers with workplaces that generate noise:
1. Permissible exposure standards: When sound from machinery and equipment in a workplace exceeds 90 decibels, employers must use engineering controls and reduce exposure time so that the workers' 8-hour time-weighted average doesn't exceed the specified value; at no time may workers be exposed to impulse noise with a peak above 140 decibels or continuous noise above 115 decibels.
| A-weighted sound pressure level (dBA) | Permissible exposure time per workday |
|---|---|
| 90 | 8 hours |
| 92 | 6 hours |
| 95 | 4 hours |
| 97 | 3 hours |
| 100 | 2 hours |
| 105 | 1 hour |
| 110 | 30 minutes |
| 115 | 15 minutes |
When calculating the 8-hour time-weighted average, noise of 80 decibels or more is included on the basis that "every 5-decibel increase halves the permissible time"; when exposed to two or more sound pressure levels, the ratios of "actual exposure time ÷ permissible time" for each are added, and a total greater than 1 exceeds the permissible dose.
2. Hearing protection: When a worker's 8-hour time-weighted average sound pressure level exceeds 85 decibels or the exposure dose exceeds 50%, the employer must have the worker wear effective earplugs, earmuffs, or other hearing protection.
3. Isolation and noise reduction: Machinery that produces strong noise, such as drive motors, should in principle be suitably isolated and separated from general work areas; machinery that produces strong vibration and noise should be quieted through silencing, enclosure, vibration isolation or damping, inertia blocks, sound-absorbing materials, and similar methods.
4. Signage: Workplaces with noise above 90 decibels must be marked and display notices on preventing noise hazards.
Article 6, Paragraph 1, Subparagraph 8 of the OSH Act also lists "preventing hazards caused by noise" among the safety and health equipment and measures employers must have; Article 20 of the OSH Act requires special health checks for workers engaged in work especially hazardous to health, and whether noise work qualifies is determined by the Labor Health Protection Rules (勞工健康保護規則).
Common Ways to Reduce Machine Noise
In the order "at the source first, then along the transmission path, and personal protection last":
- Maintenance: Dry bearings, loose belts, dry chains, and loose parts all make noise louder; regular maintenance is the cheapest way to reduce noise.
- Vibration reduction: Add anti-vibration pads under machine feet and avoid bolting machines directly to steel frames or thin floor slabs that resonate; Article 42 of the Facilities Regulations also says machinery with excessive vibration should in principle be placed on the ground floor.
- Isolation: Move air compressors, refrigeration units, and vacuum pumps to a separate machine room, or add acoustic enclosures.
- Exhaust silencing: Fit silencers to the exhaust ports of pneumatic components.
- Reduce impacts: Add cushioning pads to trays and carts, and reduce drops between conveyors.
- Sound absorption: Without compromising hygiene and cleaning, use washable sound-absorbing materials on parts of ceilings or walls.
- Personal protection: For positions with a time-weighted average above 85 decibels, provide earplugs or earmuffs and teach correct use.
FAQ
Q: Are encrusting machines loud?
A: It varies with the model, speed, installation method, and maintenance condition. Noise values for Dong-Yih models aren't listed on our website; call 06-257-4644 or come to our factory to hear them in person.
Q: What are the legal noise standards?
A: Article 300 of the Occupational Safety and Health Facilities Regulations: an 8-hour time-weighted average of 90 decibels; the permissible time halves with every 5-decibel increase; at no time may workers be exposed to impulse noise with a 140-decibel peak or continuous noise of 115 decibels.
Q: When must earplugs be worn?
A: When a worker's 8-hour time-weighted average sound pressure level exceeds 85 decibels or the exposure dose exceeds 50%, the employer must have the worker wear effective earplugs or earmuffs.
Q: How can we improve a machine that's too loud?
A: First maintain it (bearings, belts, chains) and add anti-vibration pads, then isolate loud equipment such as air compressors or add acoustic enclosures and fit silencers to exhaust ports, with personal hearing protection last.