Ventac Noise Control For Schools


Published on

An overview of how poor acoustics in schools can have many negative effects on pupils. Details on how Ventac design and provide solutions to combat the affects of reverberation ensuring a much more comfortable indoor environment.

Published in: Technology, Business
1 Comment
  • Be the first to like this

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide

Ventac Noise Control For Schools

  1. 1. Noise Control For Schools www.ventac.comVentac © 2015. All rights reserved. Your Partner In Noise Control Delivering Comfort Improvement
  2. 2. Who We Are How We Can Help Ventac’s solutions can be applied to a wide variety of applications. The content below highlights the process carried out by the Ventac team for each project. Identify the problem Clearly quantifying the problem can often be the most critical step. Sometimes the noise is from an external source - such as traffic noise. In other situations, the 'hard surfaces' in the room (floor and ceiling) cause any sound generated in the room to reverberate. Our Acoustic Engineers have over 30 years experience in noise control and have completed numerous successful installations. On existing structures, the initial survey will often include detailed dimensional measurements as well as acoustic tests. We will also carry out a detailed review of any plans Final Inspection & Validation A review of acoustic performance can be carried out prior to completion. In this way we can ensure that the installation has met the acoustic design criteria. Implement The Solution Many acoustic installations fail, not because of poor materials or design, but due to fundamental errors being made in the installation. Our installations are carried out by competent tradesmen who have specialist training in noise control and acoustics. Their focus is always on ensuring that the installation meets the acoustic design criteria and ensuring the highest quality finish. Design The Solution Having clearly quantified the potential problem areas, we can then select the most appropriate solution. This solution will also take into account factors such as aesthetic requirements, room or building layout, budgetary considerations and the desired acoustic targets. reduce noise levels and optimise costs backed up by our technical ability and our research and testing facilities at Ventac. are based on transparency and the abil- ity to meet demanding business needs, on time and on budget. Headquartered in County Wicklow in Ireland with an office in The Netherlands and employing over 34 employees, the strength and depth of Ventac's resources has helped the company develop a reputation for unrivalled service and innovation. Ventac have remained consistent in providing high quality products and services with comprehensive technical support. Our value is in our ability to The Ventac Group have provided solutions and quality products to businesses and the public sector for over 30 years in many noise control sectors, building trusted relationships and helping organisations reach solutions through the use of our products. With the skills and knowledge to facilitate the most effective noise control solution across many sectors, Ventac and its team of highly skilled technical consultants offer practical bespoke solutions at affordable prices. At Ventac, long-standing relationships Page
  3. 3. Acoustics In Schools Many people feel it is important to improve acoustics in classrooms, but un- necessary to do so in those used by students with normal hearing. Yet students with normal hearing will also benefit from better classroom acoustics. Gymnasiums and cafeteria’s can be problem areas for many schools. We regularly hear complaints that this space is far too "echoey". Our products can greatly improve the sound quality in these area's where teachers and students can hear each other legibly. In classrooms, gymnasiums, indoor pools, cafeterias and other such indoor environments, poor speech intelligibility can affect learning achievement and enjoyment. A classroom with good acoustic properties will prevent noise intruding into the room as well as minimising regenerated noise from within the room. This will reduce the strain on the teachers’ voice trying to maintain control by just being heard. It also reduces stress levels for both the pupils and teacher thereby creating an ideal learning environment. Students with learning disabilities and those with auditory processing problems will particularly benefit. Another group for whom learning is especially dependent on good acoustics is young children, who are unable to "predict from context." With their limited vocabulary and experience, if they miss a few words from a teachers lecture, they are less able than older students to "fill in" the missing thoughts. Given these considerations, it is clear that a wide range of students benefit from improved classroom acoustics. Reverberation Sound quality in offices, classrooms, gyms or any enclosed space, can be compromised by high levels of reflected sound, known as reverberation. This phenomenon leads to a build-up of sound level within the space, which often has negative affects on speech communication and comfort levels. In some environments, high levels of reverberation are welcome - churches and concert halls for example. In schools however, high levels of reverberation are not desirable and can have many negative effects. Building regulations require each room or other space in a school building to be designed and constructed in a way that it has the acoustic conditions and insulation against disturbance by noise appropriate to its intended use. The sound of speech passes directly to the ears of the student via the direct sound path (as illustrated). Another part of the sound travels to various surfaces in the room and reaches students via reflected sound paths. This reflected sound reaches students from many directions at close intervals; thereby causing the reverberant effect. Effect Of Reverberation Where the reverberation is high, the student is still receiving the reflected sounds of previous syllables at the same time as they are trying to cope with the direct sound of later syllables. This makes any speech unintelligible. In many classrooms, the speech intelligibility rating is 75 per-cent or less. That means that, in speech intelligibility tests, listeners with normal hearing can understand only 75 per-cent of the words read from a list. Imagine reading a textbook with every fourth word missing, and being expected to understand the material and be tested on it. Sounds ridiculous? Well, that is exactly the situation facing students every day in schools all across the country. Solution Features  Turn Key Solutions  Low Maintenance  Cost Efficient  Installed with Minimum Disruption  Wide Range of Colours  Washable Materials  Class “O” and Class 1 Fire Rating Page
  4. 4. Measurement Of Reverberation Reverberation is a measure of how long it takes for a sound to decay. It may vary from 0.5 seconds in a normal living room, to 6 to 7 seconds or more in a large assembly hall. A classroom or teaching space with a long reverberation time of several seconds will cause syllables to be prolonged so that they overlap and hence degrade speech intelligibility. How To Solve Noise Problems Adding Ventac absorption panels, ceiling tiles, ventilation attenuation, or sound absorbing baffles will reduce the reverberation time and will improve speech intelligibility. The control and design of reverberation is based on the relative extent of sound absorption surfaces and materials that can be applied to the space. The selection of materials for reverberation control is based upon the ‘absorption coefficient’ of the material, which is a measure of the acoustic energy absorbed. Other noise control measures can be designed and installed by Ventac to reduce noise intruding from outside the room. In arriving at our recommended solutions we take into account the following:  Irish Building Regulations  Building Bulletin 93 - Acoustic Design of Schools  Acoustic test data from our acoustic laboratory  British Research Establishment (BRE) reverberation assessment software  Noise control experience gained by Ventac since 1972 Absorption Of Sound The amount of sound energy that can be absorbed by a surface is given by its absorption coefficient, α. The absorption coefficient can take values in the range 0 to 1. A surface that absorbs no sound (i.e. totally reflective surface) has an absorption coefficient of 0 and a surface that absorbs all sound incident upon it has an absorption coefficient of 1. Thus the higher the value of α, the more sound will be absorbed. Our Solutions Ventac’s solutions for noise caused by reverberation can be categorised under the following three headings:  Panel Absorbers  Ceiling Baffles & Tiles  Noise Barriers & doors The solution for every noise problem is different. Every building, or room within a building, is likely to require specific treatments in order to solve the problem. In an assembly room or classroom suffering from reverberation noise, the diagram below indicates the typical solutions we design and provide. A correctly treated room will provide the following conditions:  A more comfortable effective indoor environment  Improved student productivity and morale  An enhanced learning environment Recommended reverberation time RT (in seconds) Page
  5. 5. Check which acoustically unfriendly features you can find in your classroom:  Hard, flat, high ceilings - they provide an ideal (and unwelcome) surface for sounds to reflect.  Walls made of concrete block, brick, drywall and wood panelling – these are highly reflective and allow sounds to bounce around the classroom.  Doors left ajar - Children's voices, slamming lockers, and tennis shoe squeaks from the hallway all pour into the classroom.  Inferior doors – ones that have a hollow core or do not fit well in the frame.  A hard surfaced floor (wood, concrete, tile) reflects unwanted noise.  Objects on the wall (posters, student papers or chalkboards) reflect sound.  Easily movable furniture which scrapes the floor.  Desks too close to the walls and potential sources of external hallway or heating noises.  Teacher positioned behind a desk too far away from students.  Radiator heating that hisses and pops or inferior heating and air conditioning systems with noisy blowers or loose/vibrating parts.  Noisy buzzing fluorescent lights.  Windows open or old windows with loose frames and thin panes - a poor noise barrier between the outdoors and classroom.  Windows without coverings or hard blinds/ shades deaden reflected sounds and create ample opportunities for echoes to develop. Some Better Alternatives:  Low ceilings with Ventac sound absorbing ceiling tiles or high ceilings with Ventac absorbing ceiling baffles and high level wall panels.  Classrooms having two sets of doors.  Install hypo-allergenic carpets or area rugs on the floor.  Cover hard, sound reflective wall surfaces with Ventac panel absorbers.  Teachers stand closer to students and avoid having to increase vocal volume to be heard clearly.  An updated, well-functioning and quiet heating system coupled with a Ventac Silent ventilation system.  Acoustically friendly heating and cooling systems which feature mechanical components located away from “critical listening spaces” such as classrooms, i.e. possibly located on roof above gymnasium.  New double glazed and tightly fitting windows.  Place rubber/nylon pads on the legs of chairs, tables and desks in the classroom.  Replace or repair noisy fluorescent lights Is Your Classroom Acoustically Friendly? Page
  6. 6. Project Gallery Page
  7. 7. What our customers say ….. "“We are absolutely delighted with the vast improvement in the acoustics in our new PE Hall. It is now so much easier to work in the hall from day to day with the improvements that have been made. In addition, the coloured fabric on the walls has enhanced the hall visually. The work has also been done to an extremely high standard." - Noel Ó Gallchóir, Príomhoide, Pobalscoil Ghaoth Dobhair, Donegal "On behalf of the school, I would like to compliment Ventac on a job well done. The result is excellent as we can now hear ourselves. Once again many thanks for your professionalism and attention to detail, and I will have no hesitation in recommending your firm to others." - Eileen Burbridge, Chairperson, Kilashee School, Naas, Kildare "I found that we used to regularly excuse the noise problems and poor sound quality we had. Now we don't have to use the microphone as we can be hear at the back of the hall. Teachers have all noticed a considerable difference. There is less need for shouting and tutors and visitors to the school have all remarked on the notable difference in the quality of sound. Overall we are very happy with the work carried out by Ventac and can definitely recommend them." Vaughan Dodd, Principal, St Cronin's Boys National School, Bray, Wicklow "We highly rate Ventac's acoustic treatment as it makes a huge difference. It has resulted in our hall being less 'echoey'. Visiting schools have even noticed the difference. It is also much easier to hear what's going on when events are taking place in the hall. We are really pleased with the service from Ventac and have already recommended them to many other schools." Alice McKenna, Principal, Crecora National School, Limerick Head Office Fitzwilliam House Blessington Co Wicklow Ireland Tel: +353 (0) 45 851500 Fax: +353 (0) 45 851501 Dutch Office Hightech Automotive Campus Steenovenweg 1, 5708 HN Helmond The Netherlands Tel: +31(0) 492562130 Fax: +353 (0) 45 851501 Czech Office TRIANGL Stojanova 1334 686 01 Uherské Hradiště Czech Republic Tel:+42 0778 042862 Fax:+353 (0) 45 851501