Airborne noise resistance in both types depends on the mass per unit area of the blades, mechanical insulation (the insulation of frames or bolts) and sound insulation through the cavity and insulation (Building Regulations, 2003, British Gypsum White Book, 2015). It is important that mechanical insulation is maintained and that services, devices, etc. do not form a bridge between the two coatings. Based on the results, the acoustically profiled bridge provides a better acoustic environment. Comment: BB93 gives the upper limit for room noise level in the pool like 50 LAeq, 30mins dB. Pools usually have long reverberation times due to the nature of their construction and surface materials. This can lead to high noise levels and poor speech intelligibility (IOA and ANC, 2015). This undesirable acoustic environment exposes users and staff to exhaustive situations, especially staff who have to spend long hours in the area – employees should not be exposed to an equivalent SPL of 85 dB Leq, 8 hours for daily activities. In addition to being exposed to high SPL, they may have difficulty having normal conversations because speech intelligibility is usually impaired. Poor speech intelligibility leads to unclear and disturbed communication between staff, users or tutors and learners (Ministry of Education, 2015). To overcome this situation, people tend to raise their voices, which can contribute to the acoustic disturbance of the environment and also cause physiological and mental problems in users and especially in staff (Halle, 2016). Improving the acoustic situation by using absorbent surfaces, reducing ceiling height and avoiding parallel hard surfaces, and thus reducing reverberation time, can put an end to these adverse effects on staff and users (IOA and ANC, 2015; Halle, 2016).
Noise, which can be defined as “unwanted sound,” can increase heart rate, blood pressure, respiratory rate, and even blood cholesterol levels. Good acoustic conditions go a long way in creating a comfortable environment for staff and patients, which translates into increased staff morale, better patient privacy and the promotion of essential sleep habits – which are key elements for healing. The customer avoids a complete mechanical system and the use of natural ventilation results in a noise level of more than 40 dB, so the use of a hybrid system is recommended, which is partly based on mechanical systems and passive vents attenuated to meet the requirements. As shown in the table above, different sectors use different units of measurement to express airborne acoustic requirements. A direct conversion of the units is not possible because of the way the properties are determined. However, here is a rough conversion method to compare the requirements. Both compliance methods (PCT and DR) can be used for steel construction, although pre-completion testing is probably the most appropriate as they allow for greater flexibility in design and detail. The scope of the current range of RD for steel construction is not sufficient to include all the connection details that are typically present in a residential development.
Therefore, even if RDs have been used, there will usually be nodes where building control may require site testing. The range of RDs is constantly growing, so over time there will be fewer cases where RDs will not be able to be used. The approval process for new RDs requires significant amounts of site test data for similar details so that the tests show that the details exceed the building code requirements by an average of 5 dB and the details become public. As a result, system vendors often have little incentive to share their information if they are satisfied with the results of the PCT. Section 5 of the Scottish Building Standards Agency (SBSA) Technical Manual for non-residential buildings[8] contains acoustic requirements. However, due to the application limitations specified in the SBSA document, none of the acoustic performance requirements apply to schools. To achieve optimal acoustic performance, the connections between the partitions and other elements such as the roof, floor and exterior walls in general must be carefully described in detail. It is recommended that the wall continually extend to the bottom of the roof. The connection between the partition and the roof had to be filled with flexible formwork (Building Code, 2003).
Robust details have been developed as an alternative to the PCT. A number of details have been developed that have been proven by testing to consistently meet (and exceed) the acoustic performance requirements set out in the approved document E[3]. The available RDs and their specification requirements are listed in the Robust Details Handbook[7] of Robust Details Limited. To use a Robust Detail E part in the construction process, builders must first obtain permission from Robust Details Limited and pay the required fee for each apartment. Provided the sturdy details are constructed correctly, this will be accepted by building inspectorates in England and Wales as proof that the houses are exempt from the PCT. Background noise: Noise and speech confidentiality are two important factors in the acoustic environment of the office (Jensen, Arens and Zagreus, 2005). Ambient silence can be as distracting as a noisy environment as it highlights acoustic interference and reduces speech intimacy, so ambient noise levels can be useful as they can help mask speech from an adjacent room and improve privacy. Listening to private conversations in offices has been cited as one of the leading causes of acoustic dissatisfaction in open-plan offices, where moderate noise levels can help mask acoustic privacy. Sound masking systems provide low levels of background noise to provide workers with a certain level of confidentiality in their communications and can reduce the distraction of hearing interruptions (International Well Building Institute, 2017). In practice, the required background noise is generated by mechanical ventilation systems or by the installation of a speech masking system.
Privacy protection improves when the continuous background noise level is increased, but with a higher background noise level, the likelihood of employees being disturbed increases. Choosing an appropriate background noise level requires a balance between these conflicting ideas. Workplace noise reduction rules[15] are the main pieces of legislation applicable to industrial buildings. Other regulations that contain noise requirements for industrial buildings are the Occupational Health and Safety Act[16] and the Pollution Control Act[17]. Retail space varies enormously in nature, e.B. from small individual stores to large stores to open malls and retail stores in the industrial warehouse style. The type of retail space affects the desired and acceptable acoustic properties and the solutions used to achieve these characteristics. Ministry of Education (2015) Acoustic Design of Schools: Performance Standards, Building Bulletin 93. Available at: www.gov.uk/government/publications/bb93-acoustic-design-of-schools-performance-standards. BB93[1] specifies the acoustic performance of floors for impact sound for different types of rooms (see following table).
Sound insulation against impact must be designed and measured for floors without soft cover, e.B. carpet, vinyl covered with foam, with the exception of concrete floor floors where soft cover is an integral part of the floor. Outdoor noise penetration levels must not exceed the following criteria for acoustic design after attenuation by the composite building envelope: This article examines the UK`s acoustic requirements for residential and non-residential buildings. This may include regulatory requirements, but also industry documents such as Construction Bulletin 93[1] for schools and HTM Health Technical Memorandum 08-01[2] for hospitals. The focus is on requirements that are influenced by the structural form and construction details, not on internal surfaces and construction services. Using the approximations presented above, a new table has been created that expresses all the requirements for airborne sound insulation compared to Rw for direct comparison. The data are presented in tabular form below. Open spaces require additional specifications to ensure clear voice communication between teacher and student, as well as between students, as they are complex acoustic spaces. Therefore, BB93[1] specifies a minimum voice transmission index (STI), which recommends using a computer model to predict ITS. Acoustic testing is recommended in bb93[1] to demonstrate compliance with performance requirements.
BB93[1] recommends that the client include the examination requirement in the construction contract. For the design of musical spaces in schools, the Ministry of Education published in 2010 a special design guide entitled Music accommodation in secondary schools: A design guide[9] as a revision of Building Bulletin 86 of 1997 entitled “Music Accommodation in Secondary Schools: A Design Guide”. However, for most acoustic requirements, the document refers to BB93[1]. The correct specification of materials can significantly affect the acoustic performance of the room and the atmosphere created. This is especially true for large open spaces such as car showrooms, in areas with large hard areas, and in stores where the quality of the music and/or sound system is important. Table 7: Well Building Standard Credits for Acoustic Performance (International WELL Building Institute, 2016) Two acoustic products: Noise reduction treatments that include absorbent surfaces such as wall panels, ceiling deflectors and surface improvements can help with reverberation management and improve acoustic comfort (WELL Building Standard, 2017). . . . .
