Shooting Range Acoustic Consulting & Noise Control

Shooting Range Acoustic Consulting & Noise Control

Shooting Range Noise Sound transmission from gun ranges has become a growing concern as shooting sports increase in popularity, and firing ranges are built in close proximity to retail areas and residential districts. We work with developers, architects, engineers, and city planners to evaluate potential noise concerns from shooting facilities. Wave Engineering, Inc. evaluates new and existing ranges with computer modeling and on site sound measurements, and can assist with exterior noise, permitting, and compliance with state and local noise codes and ordinances. We can also recommend acoustic treatments to control noise and reverberation inside the range, retail, and classroom areas. For more information, please watch our video profile on gun range noise and acoustics, below… HVAC systems shown in this video are by Carey’s Small Arms Range Ventilation. To Get Help With Your Shooting Range Project Contact Us...
Sound Masking for Speech Privacy

Sound Masking for Speech Privacy

Many open office areas employ electronic sound masking systems to create an even distribution of background noise that is just loud enough to help mask distracting noises (particularly from other conversations) without being loud enough to be a nuisance. The system typically consists of special loudspeakers mounted in or above the ceiling and a head-end unit that generates and shapes the noise. Another useful application of sound masking is to improve speech privacy between rooms. Privacy is traditionally assessed simply by using the Sound Transmission Class (STC) of the partition between two rooms. However, this is only part of the picture. Privacy is dictated both by how much sound passes through the partition (STC) and the background noise level in the receiving room. Obviously, it is easier to eavesdrop on a conversation if the receiving room is quiet. There are many situations where privacy is important and the background noise level can be used to our advantage. Speech privacy is important in healthcare where HIPAA requires that “reasonable safeguards” be taken to protect the privacy of patients’ personal healthcare information. The 2014 FGI Guidelines for Hospitals and Outpatient Facilities acknowledges the effect of background noise on privacy in the STC requirements between Exam Rooms. Table 1.2-6 requires STC 50 between Exam Rooms unless there is an electronic masking system, in which case only STC 40 is required. A 10-point difference in the STC rating is significant, and it may be less expensive to build STC 40 walls and install a sound masking system in an exam area than to build STC 50 walls and no masking. Sound masking can...
Beware the Gypsum Association Manual STC Ratings

Beware the Gypsum Association Manual STC Ratings

Do you select Sound Transmission Class ratings from the Gypsum Association Fire Resistance Design Manual? The GA manual contains a lot of good information on fire and sound ratings. The sound ratings, however, must be used carefully. Knowledgeable acoustic consultants do not rely on the GA manual Sound Transmission Class ratings, but use laboratory test reports (multiple reports when available). We may also supplement the lab test reports with field test reports and calculations. Our goal is to determine the most likely average rating for a wall or floor-ceiling. STC tests, even in a laboratory, are not perfectly repeatable. The same wall can be tested in five different labs with five different results. The same wall can be tested multiple times in the same lab and yield different results. Wall construction isn’t perfect and the test method isn’t perfect. Multiple tests of the same wall usually follow more or less a bell curve distribution.     The Gypsum Association categorizes a partition based on one lab test result. The GA categories are typically STC 45-49, 50-54, 55-59, etc. The STC range given by GA is not the range of STC test results for a particular wall. It is simply the category that GA has assigned that wall to. GA gives no indication whether a particular wall falls at the low or high end of that category and a 5-point difference in STC ratings is significant. Unless you research and find the specific lab test referenced by Gypsum Association, you won’t know if your wall’s test is at the high end or the low end of the GA category. Partitions...
Cushioned Vinyl Floor Test – Time Lapse

Cushioned Vinyl Floor Test – Time Lapse

Vinyl flooring options have expanded in recent years to include finishes that mimic the appearance of tile and hardwood. These materials have become popular in multifamily condominium and rental apartment markets, and hospital and healthcare facilities (long term care, hospice, etc.) due to the attractive cost and low maintenance. As acoustical consultants, we evaluate flooring materials as they relate to sounds in the room and impact noise transmission between rooms/units. Hard floors transmit impact noise more easily to the room below, while softer materials like carpet can reduce impact noise transmission. Cushioned vinyl can also result in less noise from footfall, cart traffic, etc., in the room above, which is advantageous in hospital patient rooms and corridors. This is beneficial to both patients and hospital staff. To help improve the impact noise isolation performance of their products and make them more attractive in the market place, flooring manufacturers have been adding integral resilient underlayments and pads to vinyl flooring. These underlayments are usually made of rubber or foam. While these materials do reduce impact noise transmission, our clients expressed concern as to how the material will be affected by heavy furniture, and if permanent marking or imprints will be left on the surface. We tested Ecore’s Forest Rx Vinyl Flooring, by placing a metal desk on a product sample for more than three weeks. The foot of the desk left a deep impression in the vinyl. As we removed the desk from the sample, we recorded a time lapse of the product sample/desk impression. See the video, below. We stopped our time lapse a little over seven hours. While the indent...