The HSE has just released new guidance on how best to manage the use of hearing protection for employees who wear hearing aids. The following is a summary, but you can also download a full advance copy. There are key considerations when implementing a hearing conservation programme in areas that include personnel who already have a hearing impairment and may need to use hearing aids. Would switching off my hearing
Fan noise reduction – efficiency gains without attenuators
Award Winning Fan Noise Attenuation Technology
Fan noise reduction technology reduces capital cost by 80% – 90% and reduces running costs
The performance and efficiency of industrial fans is often seriously compromised by fan silencers, particularly for low frequency noise problems. We have developed alternative technologies that reduce the noise at source and can also improve system efficiency… We have also developed remote analysis techniques that allow us to apply our fan noise attenuation technology anywhere in the world via the internet.
Imagine using self-financing technology to eliminate environmental fan noise problems
We can reduce industrial fan noise and improve system efficiency using aerodynamic technology instead of attenuators, not only at a fraction of the cost of fan silencers, but the efficiency gains can often make fan noise control projects profitable. Typical project savings are an 80% reduction in capital costs and a 20% efficiency improvement* with minimal down-time required for installation.
How does the fan noise control technology work?
F1 and aerospace engineers use aerodynamic aids to enhance performance. We’ve developed similar technology to model fan systems and design retro-fit aero-inserts that reduce noise from existing fans at source. This reduces the noise travelling down both the intake and exhaust duct-work as well as that passing through the fan casing which can eliminate fan silencers, lagging and conventional acoustic enclosures.
Silencing Performance and Costs
80% reduction in capital cost, 20% efficiency improvement*
The modifications last the lifetime of the fan without maintenance and can be retro-fitted with very little down-time. Applications include ID and extract fans, chillers, air conditioning plant, process and ventilation fans, HVAC systems, power stations, cement and steel works and most fans where there are low frequency noise issues.
For more information visit – Fan Noise Control
*typical large fan, low frequency noise control applications versus typical conventional fan silencers e.g. $1.25 million refinery project silencer cost reduced to $250k.
How to benefit from the technology
We can provide a free evaluation of the potential for our technology on any stack / fan system anywhere on the globe if you can provide us with photos and data from any smartphone by email or over the internet.
Innovative fan noise reduction examples
Award Winning Tata Steel OG Fan Noise Reduction – £1,000,000 cost savings
Three, 4 megawatt fans generated a low frequency hum over a wide area. As the fan speeds vary, resonator silencers were ruled-out and conventional attenuators would have reduced fan efficiency and been incredibly costly.
A second opinion saved a £million…
Our approach involved aero-inserts inserted into the fan casings (no need to modify existing ducts or stacks to fit silencers) with minimal downtime. The fan modifications require no maintenance and improve the efficiency of the fans compared with attenuators.
“The modifications hugely reduced the fan noise across a wide area around the plant. They’ve also saved us a large amount of money by negating the requirement for major capital expenditure, so it’s been a remarkably successful project.” – Grahame Wallace, Tata.
Biomass Power Station – more fan efficiency, less noise and cost
The huge ID fan feeding the stack (shown below) at the 50MW Schiller biomass power station (the largest in the USA) had a serious fan noise problem over a wide area. The company sought us out to see if there was an alternative to an energy sapping silencer. The fan was modified in only 12 hours (not a misprint – just 12 hours from noisy to quiet) to reduce fan noise by 10dB at tiny fraction of the cost and with much lower power consumption compared with the conventional fan attenuator previously fitted.
It seems almost too simple – it may be difficult for industry to get used to the idea that instead of the massive engineering structures and the extensive and therefore costly down-time historically assumed to be required to reduce fan noise, it is often possible to insert elegant aerodynamic aids inside the fan casing within a few hours to eliminate the noise problem at source. All this without compromising fan efficiency as is often the case with conventional fan silencers.
Record Breaking F1 Fan Noise Control
The option to fit fan silencers to this extract system seemed a slow process to a company used to the pace of Formula One. Red Bull found an alternative in our aerodynamic noise control technology. The aero-inserts were installed inside the fan casing within a pit-stop period of a few hours, reducing the 218Hz low frequency tone by a factor of around 1000 (30dB – a new record for the technique). This completely eliminating the problem for the lifetime of the fan, without maintenance and without affecting fan efficiency.
“We felt that there had to be a better way to reduce the fan noise other than by compromising the system efficiency by using fan silencers and also creating additional long term maintenance” said Terry Brice of Red Bull Technology. “The INVC technique not only produced a fantastic result, but it’s also s very satisfying and elegant engineering solution”.
Roof-Top HVAC – air conditioning chiller noise control at 10% of the cost
The quote to reduce air conditioning system chillers noise on the roof of a facility to meet environmental noise specifications was over £300,000 (including street closures, and cranes). The conventional silencing and screening would also have reduced the cooling capacity of the HVAC system.
The company approached us in the hope that we could provide a second opinion. We developed an elegant solution for the air conditioning units that involved a combination of engineering control at source, innovative local acoustic treatments and the clever use of geometry. These modifications were very easy to implement (all components could be bough up in the lift) and reduced the condenser axial fan noise by 15dB(A) at a cost of c £40,000 – and with no effect on the efficiency of the system.
Plating Plant Cooling Tower Noise – acoustic un-screening…
Two new cooling towers had caused complaints from residents near the site. The company had been advised to fit a conventional acoustic package comprising silencers and a barrier at a total cost of around £30k (and with serious access issues) with a predicted noise level at the neighbours of around 56dB(A) – still too high for the area. Our solution was a combination of engineering source control in a package for both cooling towers and pumps that reduced noise levels to <50dB(A) at a cost of only £5k.
Remote control of fan noise – anywhere
We have developed the technology to diagnose fan noise problems and to provide solutions anywhere in the world via the internet – without a site visit. This saves time and money and gives the whole world access to our innovative power saving fan noise control technology. We’ve completed many very successful planet-wide projects from our offices, including this oil refinery in the USA where the quoted fan silencer capital costs were reduced from c $1.25 million to c $0.25 million…
Contact us for details or a free fan noise analysis evaluation
* = Required