Introduction: excessive noise in an industrial plant – hidden risks
Noise in a production plant is a serious problem that can generate more costs than you think. Exceeded noise standards are not only a risk of severe financial penalties but, more importantly, a silent enemy that undermines employee safety, badly affects their health and operational efficiency. The effects of exposure to excessive noise include reduced ability to concentrate, impaired perception of warning signals, increased risk of accidents and even long-term health problems such as cardiovascular disease or increased risk of type 2 diabetes.
Occupational noise, often reaching very high levels in many industries, especially industries such as heavy industry (up to 134 dB), or machinery (up to 125 dB)(1). This is why it is crucial to find solutions that ensure effective noise reduction in a production facility without causing production downtime or generating skyrocketing costs.
In the following case study, we discuss how we solved the challenge of exceeding noise standards in a wood processing plant. Our task was not only to significantly soundproof the production machinery, but more importantly to ensure full compliance with stringent standards and improve working conditions.
The client’s challenge: disruptive machine noise at a wood processing plant
Our client, a large wood processing plant, was facing the problem of excessive noise generated by key woodworking processes such as milling, drilling and sanding.
The processing of a large number of workpieces is carried out in a continuous process that allows large volumes to be produced and wood boards to be processed simultaneously from both sides. For these processes, open-architecture machines are used, in which the source is not separated from the operators. Although open-architecture machines improve overall productivity, they have a major negative impact on staff productivity.
Sound levels in the hall exceeded current standards, posing risks to staff health and safety, as well as potential legal implications.
Standard solutions: why couldn’t they be used?
TTypically, the most common technological solutions for noise reduction are designs that completely enclose machines in acoustically hermetic enclosures.
Such enclosures can provide a high level of noise reduction, but only if the enclosure has no openings or penetrations. For continuous flow production lines, this is impossible to implement. In addition, there would have to be enough space around the machine itself to accommodate this bulky design. In addition, an enclosed machine could generate too much heat, and one of the additional requirements was that the acoustic solution introduced would allow remote control and monitoring of the machine.
Implementing a traditional solution would have required significant modifications to the production process, limited the functionality of the line and easy access to the machines and, above all, would have entailed costly downtime.
The customer also needed a solution that, in addition to those mentioned, would meet the following specific requirements
- Low-frequency effectiveness: the acoustic panels had to be highly effective in attenuating noise, especially in the low frequency range, where sound reduction is particularly difficult.
- Thin design: the solution had to be compact and not interfere significantly with the space around the machines.
- Maintenance of machine accessibility: the enclosures could not block access to the machines or impede their operation.
- Regulatory compliance: the overriding goal was to reduce noise levels to values that comply with local regulations, including European Union Directive 2003/10/EC, which sets an upper limit for continuous noise exposure (85 dB) for operators.
Such a challenge required a customised approach and the application of precision acoustic engineering to ensure effective noise reduction without disrupting key production processes.
The Silencions solution: innovative acoustic panels for industry
The core of the Silencions solution: an advanced combination of traditional acoustic materials and mathematical materials
With our own fully equipped laboratory and a team of experienced acousticians, we were ready to take immediate action. We conducted noise measurements and then designed and manufactured dedicated thin acoustic panels based on these measurements. We used a combination of innovative metamaterials and traditional acoustic materials in the design, thus achieving maximum performance.
The metamaterials technology is based on an intelligent acoustic material that outperforms conventional solutions, providing exceptional noise and vibration reduction. The combination of the characteristics of both types of material shows great potential for noise dampening. It also offers the possibility to create panels that are extremely thin (even less than 1 cm thick), yet extremely effective in damping noise – including problematic low frequencies that conventional solutions often cannot handle.
What’s more, our technology is material-independent, allowing panels to be manufactured from a wide variety of raw materials, such as recycled plastics, metal, wood or transparent materials, while maintaining low weight and volume and good heat convection. This combination of material properties and unique geometric design makes our panels extremely versatile and customisable.
Key advantages of our technology:
- Intelligent acoustic material: the basis for exceptional noise and vibration reduction.
- Higher efficiency: the combination of metamaterials with a traditional acoustic insert allows noise to be dampened over a wider range Surpasses conventional solutions in sound dampening.
- Extremely thin panels: thickness as thin as less than 1 cm for minimal interference with space.
- Low-frequency effectiveness: effective damping of difficult low-frequency tones.
- Material independence: can be manufactured from recycled, metal, transparent materials.
- Low weight and volume: easy to install and adapt.
- Good heat convection: ensures optimal machine operating conditions.
- Versatility and personalisation: customised panels for individual needs and applications.
Safe and compact: non-combustible acoustic panels with a thickness of less than 3 cm
The layered configuration of the Silencions panels combines the advantages of each layer. The bottom layer contains a tuned Silencions metastructure, which attenuates low frequencies (typically below 1 kHz). The material just above the metastructure improves acoustic absorption at higher sound frequencies. The top layer is fibre wrapped to improve the overall non-flammability requirements of the manufacturing facility. The layered configuration of the Silencions panels is less than 30 mm thick and is enclosed between the panels, thus creating a thin yet secure acoustic enclosure.
Effective protection against adverse environmental conditions
Silencions technology has made it possible to selectively target and reduce problematic noise frequencies using sound-absorbing material to reduce overall broadband noise levels and protect against adverse working conditions.
We implemented the solution directly around the HOMAG woodworking machine, which consists of two symmetrical modules placed on either side of a conveyor belt transporting wooden boards in a continuous production line.
The installation was carried out with the utmost care to maintain the full functionality of the machine and minimise disruption to the production process. Our flexibility and responsiveness allowed the work schedule to be tailored precisely to the client’s needs, ensuring that production continuity was maintained.
Results and benefits: silence proven by the numbers
Once installation was complete, we paid particular attention to checking the effectiveness of the installed panels in the area where the operator usually stands while the machine is running.
Following the installation of the Silencions panels, a clear reduction in noise levels was observed across the measured spectrum, together with a reduction in narrowband noise.
Measurements of the equivalent sound pressure level (LAeq) at 8 strategic locations around the HOMAG machine confirmed the outstanding effectiveness of the Silencions solution. The sound pressure level (LAeq, in dB) measured in the vicinity of the GUI panels and in locations where operators spend most of their working time during machine operation was compared before and after the installation of the Silencions panels.
- Significant noise reduction: a reduction in LAeq of up to 6.1 dB was recorded, and sound pressure levels were reduced by at least 4 dB.
- Full compliance with standards: at each measurement location, sound pressure levels fell below the 85 dB value. This is an important value, described in the European Union Directive 2003/10/EC as an upper value for continuous noise exposure over an 8-hour operator working day.
- Improving operators’ working conditions: In the operators’ workplaces (left and right side of the machine), the sound pressure level has been reduced by at least 4 dB, which is key to meeting the requirements of the EU Directive 2003/10/EC on long-term noise exposure.
A comparison of the one-third octave bands at site 2 (left) shows the reduction in sound pressure levels across the expected frequency range. The high reduction in the 800 Hz and 1250 Hz bands was achieved by a special metastructure tuned to the most problematic frequencies generated by the woodworking machine.
The graph below shows the measured A-weighted sound pressure level spectrum in front of the control panel, which the operator usually stands in front of when the machine is running.
By implementing Silencions panels, the customer also gained a number of additional tangible benefits:
- Compliance with health, safety and environmental regulations: eliminating the risk of penalties and ensuring a safe working environment.
- Improved employee comfort and productivity: noise reduction directly translated into improved staff wellbeing and increased operational efficiency.
- No long production downtime: the installation was carried out in such a way as to avoid long and costly downtimes (we only needed 1 day for installation and measurements).
- Long-term investment: the panels used are a durable, aesthetically pleasing and functional solution that does not restrict access to machinery, ensuring ease of installation and maintenance.
- Proven effectiveness: the data and reports obtained provide solid proof of the effectiveness of the solution, which can be presented to auditors or the authorities.
Summary: Silencions – a partner for solving noise problems
The above case study is an example of how we at Silencions Acoustics Laboratory successfully solve complex acoustic problems in industry. Our knowledge-based approach, combined with hands-on experience and flexibility, allows companies such as wood processing plants, large manufacturing companies, as well as institutions or retail chains, to reduce noise emissions, improve working conditions and at the same time maintain business continuity.
Find out what you gain by choosing Silencions as your proven partner in solving noise problems:
- All services in one place – you save time and resources: with us, you do not need to involve multiple companies. We offer a full range of services: from precise noise measurements to design and implementation of dedicated solutions.
- Expert knowledge: our specialists are well versed in acoustic regulations and standards, ensuring that every solution complies with the law and providing support in interpreting complex regulations.
- Ongoing expert care: you receive full support and the opportunity to consult with acousticians, at no extra charge.
- Clear and easy-to-understand reports: we present our findings in a clear format to help you make informed decisions and communicate quickly.
- Flexibility and responsiveness: we will tailor project times to your needs. We are able to help even with urgent matters. We minimise downtime and ensure business continuity.
- Mobility: we are able to travel anywhere in Poland and Europe to carry out on-site measurements and implementations.
- Fast quote: you will receive a detailed adaptation quote in as little as 3 days. This will allow you to plan efficiently and effectively based on specific data.
- Experience of working with large partners: we have a proven track record of implementing complex projects for industrial companies and institutions.
Turn noise into silence — contact us!
Are you facing a similar challenge with noise at your company? Do you need measurements, expertise or a dedicated acoustic solution that will not disrupt your production?
Contact us! Our specialists are ready to help you find the perfect solution and meet any acoustic challenge.
We are available on working days from 7:00 a.m. to 5:00 p.m.
(1) Bortkiewicz A, Czaja N. Pozasłuchowe skutki działania hałasu ze szczególnym uwzględnieniem chorób układu krążenia. Forum Medycyny Rodzinnej. 2018;12(2):41-49.