Stc vs oitc sound transmission. It is especially important in commercial construction.

Stc vs oitc sound transmission STC 0 10 20 30 40 50 60 70 0 10 20 30 40 50 60 70 C STC. Like the STC rating, OITC measures sound intensity loss in decibels. STC 30-40: Loud speech can be heard, but not entirely clear. But is it useful for What are STC and OITC? Sound Transmission Class & Outdoor/Indoor Transmission Class. STC Ratings for Load-Bearing Walls. Mecart’s standard acoustic products are labelled STC-35, STC-45 and STC-52. The OITC rating was developed in 1990 and is typically used to measure sound transmission loss over a frequency range from 80 to 4000 hertz. Ratings span: STC Ratings from 39 to 48; OITC Ratings from 34 to 44; These figures mean CitiQuiet windows can decrease exterior noise anywhere from 50% up to nearly 80% What we mean when we say STC-35, STC-45 and STC-52. The increased interior pane thickness of STC/OITC glass can dull noise to transform your home environment. Sound Transmission Class (STC) STC (Sound Transmission Class) represents a material or product’s ability to block sound from travelling through a wall, ceiling, floor or other building assembly – in other words, to stop airborne noise transferring from place to place. It is especially important in commercial construction. STC is decibels (dB) reduction in noise a material/ partition can provide. 1 Sound transmission loss as defined in Terminology C634, refers to the response of specimens exposed to a diffuse incident sound field, and this is the test condition approached by this laboratory test method. OITC has been adopted based on the assertion that it is more reliable than STC. Higher ratings mean a greater resistance to sound penetration. 1 3/4″ doors (lightweight for STC doors) Any manufacturer’s hinge locations; 16-gauge steel A40 galvannealed standard; ANSI A250. Understanding Sound Transmission Coefficient (STC) Ratings in Windows. The OITC is for outdoor / indoor transmission class that measures the sound transmission between outdoor and indoor structures. In typical metal building construction the values for STC range from a low STC (Sound Transmission Classification) Overview. Sound Transmission Class (STC) rating system measures sound transmission loss between 125 Hz and 4000 Hz. It. 3 Sound transmission loss –TL. The Outdoor–Indoor Transmission Class (OITC) is a standard used for indicating the rate of sound transmission from outdoor noise sources into a STC is typically used to measure sound transmission loss over a frequency range from 125 to 4000 hertz, and is most applicable for interior areas that experience mid to high frequency noises, such as conversation, Like the STC rating System, OITC measures sound intensity loss in decibels. sound transmission loss properties of a wall or roof is the sound transmission class (STC). Two sound ratings are mainly used: sound transmission class (STC) and outdoor indoor Sound Transmission Class (or STC) is an integer rating of how well a building partition attenuates airborne sound. Sound Transmission Class (STC) is a single-number rating of the airborne sound transmission loss (TL) performance of a What an OITC Rating is, why it is important, OITC vs STC, and examples of noise levels you can expect with different OITC and STC ratings. Department of Housing and Urban Development offers resources and information on housing programs, policies, and assistance for individuals and communities. com; Tài khoản Đăng 5. For more information on the ratings provided, please see the definitions below. Sound Transmission Class (or Is OITC Better than STC? The short answer is ‘No’. The OITC (Outdoor Indoor Transmission Class) rating was created to test exterior walls and their elements (windows and What is STC? Sound Transmission Class (STC) is an integer rating of how well a building partition attenuates airborne sound. Images courtesy • Sound Transmission Class (STC) • Outdoor-Indoor Transmission Class (OITC) 13 Sound Transmission Loss (STL) The STL is a measure of the reduction of the sound intensity (dB) from one side of a barrier to the other. Product Series. This rating is given to materials that are tested over a range of frequencies, and are proven to block sound in some capacity. Client . 5” Resilient Channels RC Deluxe, 16” OC Assembly Number: ISS-08 STC: 45 OITC: 29 NWTL140829-01 STC 45 5/8” gypsum Size 24” oc AFB Thickness Penetrations Electrical Boxes Included Acoustics Assembly STC rates sound transmission over a frequency range (from 125 to 4000 hertz) and is applicable to interior areas that experience OITC rates sound transmission from exterior to interior areas across a frequency range of 80 to 4000 hertz and therefore is applicable for low-frequency noises, most commonly coming from urban environments, such as road traffic, aircraft, railroads, number that represents the measured sound transmission loss (TL) obtained in accordance with ASTM E-90-02 Standard Test Method for Laboratory Measurement of Airborne Sound Transmission Loss of Building Partitions and Elements. As such, it is calculated over the frequency range of 125 to 4000 hertz. What is STC, OITC , and IIC. Soundproofing Tips; Materials; The tests collected both the Sound Transmission Class (STC) and Outdoor/Indoor Transmission Class (OITC) values for each of the wall assemblies. STC is typically used to measure sound transmission loss over a frequency range from 125 to 4000 hertz, and is most applicable for interior areas that The OITC rating represents transmission loss results from 80 to 4,000 Hz using a different mathematical equation than the STC rating. OITC vs. It is the most common sound measurement system in North America – that’s why you’ll see it OITC is calculated by subtracting the logarithmic summation of the transmission loss values from the logarithmic summation of the A-weighted transportation noise reference spectrum stated in the calculation standard. The OITC (Outdoor Indoor Transmission Class) rating was created to test exterior walls and their elements (windows and Sound Transmission Loss ratings# STC# STC or Sound Transmission Class is a single number rating for partitions. The first is the STC rating. STC stands for sound transmission class. TL Def. Donate; materials, construction, and methods to STC and OITC rating for concrete masonry and clay masonry The updated version of this Standard provides minimum requirements for rating masonry walls for a sound transmission class (STC) and added for 2012 outdoor-indoor transmission class (OITC) based on field or laboratory testing or based on a calculation procedure. Most double-glazed windows will achieve an STC number in the mid- to high-20s. STC được xác định bằng cách (+84) 93 867 2708 - (+84) 98 415 3162; support@rockwoolkhaihoan. A relatively new way of measuring sound transmission, an OITC rating (which stands for Outdoor–Indoor Transmission Class) provides information about how well a barrier blocks against certain types of frequencies. What is Sound Transmission Class (STC)? STC – Sound Transmission Classification. STC ratings are The higher the STC or OITC value, the lower the magnitude of sound transmission through the barrier. OITC The STC (Sound Transmission Class) rating was created to provide a rating for interior building partitions that are subjected to noises from mid to high frequency noise sources. The TMS 302 Sound Standard provides minimum requirements for rating masonry walls for sound transmission class (STC) and outdoor-indoor transmission class (OITC) based on testing calibrated calculation procedures. On the low end of the scale, you will be able to hear voices but not the content. The reduction in sound level at specific frequency levels when sound passes through a door assembly. When it comes to sound-absorption measurements, manufacturers generally use one of two standards approved by the American Society for Testing and Materials (ASTM): the Sound Transmission Class (STC) and Outdoor-Indoor Transmission Class (OITC). There is a difference between STC and FSTC (Field Sound Transmission Class) ratings. IIC is used to measure the impact sound insulation of floors, while NRC is used to measure the sound absorption capabilities of materials. It is important to understand the nuances of sound transmission class ratings and how they relate to real-world noise control options. Learn what you need to know and check out our STC rating chart today! While originally developed for speech privacy, sound transmission class (STC) ratings have become a standard of design for spaces where acoustics are a concern and the most common sound reduction The ASTM measurement system has three basic divisions: STC, CAC, and OITC . When measuring OITC, a sound source generates sounds at predetermined frequencies and the receiver measures what it hears. STC ratings range from 0 to 100. In the US, it is widely used to rate interior partitions, ceilings, floors, doors, windows and exterior wall configurations. Essentially, it’s the report card of a structure’s ability to reduce noise. For example: if a 300 Hz, 80 dB sound on one side of a wall is reduced to 30 dB on the other There are two main rating systems used in the construction industry to communicate how well a product will block out sound: Sound Transmission Class (STC) and Outdoor/Indoor Transmission Class (OITC). A basic understanding of both systems will help you make more informed decisions when it comes to improving sound control in your building. CEILING Sound Proofing: STC and OITC Rating. Get sound advice from the National Gypsum technical support team In the building products industry, there are two main rating systems used to communicate how well products block sound: Sound Transmission Class (STC) and Outdoor/Indoor Transmission Class (OITC). In massive buildings there is in addition to this sound transmission, bypass noise Sound Attenuation Batt Insulation Product Data Sheet Description Acoustic Comparison of Cavity Insulation Types Sound Attenuation Batts (SAB’s) Gypsum Board Insulation Type Test Number STC are unfaced, lightweight, fl exible One layer each side. To determine the specific STC The use of sound transmission class (STC) ratings have become a standard of design. Both STC and OITC ratings inform your window or door selection based on sound insulation needs. The ISO standards give C STC – Sound Transmission Class. It measures the transmission loss (TL) of 16 different sound frequencies STC (Sound Transmission Classification) is measured in a controlled laboratory setting (ASTM E90). FLOOR SOLUTIONS. Outside-Inside Transmission Class (OITC)—measures sound transmission of low- to mid-frequency noises through exterior NRC ratings apply to individual materials tested in accordance with ASTM C423, Sound Absorption and Sound Absorption Coefficients by the Reverberation Room Method, whereas STC, CAC, IIC and OITC ratings apply only to assemblies. STC 40-50: You can 1. The long answer is ‘In some cases’. Assess your specific requirements and A brief review of acoustic ratings. An STC test is usually carried out in controlled laboratory conditions, and FSTCs are carried out on-site or ‘in the field’. Sound Transmission Class (STC) is a The OITC rating system measures the transmission of street sounds (such as car horns, sirens, construction, and low-flying airplanes) through exterior walls, windows, doors, and other facade elements. Sound Transmission Class (STC): The higher the STC number, the more efficient a window is at blocking outside noise. The document discusses methods for calculating various acoustic ratings including STC, RW, MTC, and OITC. It is calculated or derived from 1/3 octave band Sound Transmission Loss data by a method described in American Society for Testing Materials standard ASTM E413. It is the The OITC rating represents transmission loss results from 80 to 4,000 Hz using a different mathematical equation than the STC rating. STC •Average difference STC –OITC = 6. The CAC is the ceiling attenuation class which is for ceiling structures. The higher STC/OITC rating of the window assembly will typically be reduced from the base glass acoustical rating. The results express in decibels as opposed to the point system used to determine STC ratings and To determine how much sound is transmitted through a window, manufacturers conduct testing to calculate ratings for two primary ratings: Sound Transmission Class (STC) and Outdoor/Indoor Transmission Class (OITC). Skip to content. These two ratings measure different frequencies, so there’s very little overlap between the two. The STC rating is based on laboratory measurements and only describes the sound transmission through a single building element. STC vs. The results express in decibels as opposed to the What are STC and OITC? Sound Transmission Class & Outdoor/Indoor Transmission Class. STC stands for sound transmission classification. By taking the Sound Transmission Class (STC) Originally developed to determine the sound transmission between interior walls, STC is the original and most widely used and recognized rating system when it comes to soundproofing. The sound Andersen provides ratings for windows and patio doors' sound transmission into the home. STC indicates how well a window blocks noise. Architectural solutions to noise pollution from Dynamic Architectural Process; Projects. The sound ratings are calculated by two primary control systems: sound transmission class and Windows and doors can help block outside noises whether you live in the city or on a farm. While originally developed for speech privacy, sound transmission class (STC) ratings have become a standard of design for spaces where acoustics are a concern and the most common sound reduction Sound Transmission Control (STC) Doors; Sound Transmission Control (STC) Doors. The STC wall rating chart measures between 45 – 80. In the USA, it is widely used to rate interior partitions, ceilings and floors, doors, windows and exterior wall configurations. STC testing Sound Transmission Class (STC ) is an integer rating of how well a building partition attenuates airborne sound. OITC v. The STC (Sound Transmission Class) rating is a single-num ber rating system for Here’s what different STC ratings mean for your soundproofing needs: STC 25-30: Normal speech can be heard clearly through the barrier. The system is based on an A-weighted reduction of this transportation spectrum. (NRC), and Outdoor-Indoor Transmission Class (OITC). While the requirements in previous editions of the NBCC were given in terms of the sound transmission class (STC) rating, the new requirements in the 2015 edition are given in terms of the apparent sound transmission class (ASTC) rating. Outdoor/Indoor Transmission Class (OITC): To find OITC, sound is played at a predetermined frequency from 125 hertz to 4000 hertz. Below is a summary of each of these sound transmission classes and how they might relate to your project. What is STC? STC stands for Sound Transmission Class and is measured to calculate the effectiveness of soundproofing materials in reducing sound transmission between rooms. S. Common STC Ratings. The method The four types of sound ratings referenced on this site are STC, OITC, IIC, and Delta IIC (ΔIIC). com Conclusion: A person cannot detect a change in loudness of +/- 1 dB (STC). • 1/1 or 1/3 octave transmission loss (sound Common SNQ values include Sound Transmission Class (STC) and Outdoor-Indoor Transmission Class (OITC). 2 Outdoor-Indoor Transmission Class. To determine how much sound is transmitted through a window, manufacturers conduct testing to calculate ratings for two primary sound control systems – Sound Transmission Class (STC) and Outdoor/Indoor Transmission Class (OITC). OITC ratings, on the other hand, evaluate outdoor-to-indoor sound Transmission Class (OITC) rating describes its approximate decibel level reduction of sounds such as those of roadway and rail traffic, and of nearby aircraft takeoffs. The higher the rating, the most effective the material or assembly is at blocking sound. Outdoor/Indoor Transmission Class. The OITC rating is used to measure the sound transfer between outdoor and indoor Sound Rating. Sound Transmission Class (or STC) is an integer rating of how well a building partition attenuates airborne sound. For glazing that is installed within a building interior, the Sound Transmission Class (STC) rating may be a more appropriate measure, as it describes the approximate decibel level reduction for the sound of The definitions of two ratings: Sound Transmission Class or STC and Outdoor-Indoor Transmission Class or OITC; The project’s design requirements and how they impact the glazing system, and; How to calculate an STC or OITC rating; Source: STCratings. Topics covered include reference standards, definitions and notations, materials, construction, and methods to STC and OITC rating for concrete masonry † STC (Sound Transmission Class) – used to rate air transported sound transmission between two areas separated by an interior wall or in comparing the sound transmission ratings of building assemblies using different materials: STC, IIC and OITC data to request permission to obtain the underlying independent report to ensure that the tested data is meeting the code Sound Transmission Class (STC) Rating. STC is the oldest and most widely recognized sound control rating system in the window industry. (Hz) (dB) (dB) 80 25 100 27 125 31 4 160 34 4 200 34 7 250 39 5 315 43 4 400 44 6 500 49 2 630 52 - 800 57 - 1000 61* - 1250 61 - 1600 64* - 2000 59 - 2500 58 - 3150 64 - 4000 72* - Sound transmission through the filler wall exceeds correction limits established in ASTM E90; therefore the result is "an estimate of the lower limit". 4. The test results are therefore most directly relevant to the performance of similar specimens exposed to similar sound fields. Sound Reduction Index (SRI) is defined in ISO-140 (2012). About TMS. 5” Resilient Channels RC Deluxe, 16” OC Assembly Number: ISS-08 STC: 45 OITC: 29 NWTL140829-01 STC 45 5/8” gypsum Size 24” oc AFB Thickness Penetrations Electrical Boxes Included Acoustics Assembly Description. As previously explained, this means they have been tested in a laboratory for their sound transmission loss. J2247-11-303-11-R0 Insulation Included: ROCKWOOL AFB 45 5/8” gypsum 3 5/8” Steel Stud Spacing 16” oc AFB 3. Sound Transmission Class (STC) rating, calculated according to ASTM E413, measures the sound insulation of a window or door across the frequency range of 125 to 4000 HZ, primarily covering human speech frequencies. The overall STC rating is an average of the STC ratings measured between 125 Hz and 4,000 Hz. The STC (Sound Transmission Class) rating is a single-number rating system for The sound transmission class (STC) is taken to be the transmission loss value, measured in decibels (dB), corresponding to the intersection of the reference curve and the 500 Hz frequency line. STC and OITC calculations both use 1/3 octave data generated from the ASTM E90 sound transmission loss test. The apparent sound transmission class (ASTC) rating quantifies the sound transmitted directly through the separating wall assembly as well as indirectly via the adjoining building elements, as shown on the right. CitiQuiet utilizes advanced testing methodology to determine precise sound dampening capabilities via Sound Transmission Class (STC) and Outdoor-Indoor Transmission Class (OITC) ratings. 5 fi berglass insulation batts, ⁄8" None TL-92-618 38 5 designed to deliver noise control ⁄8" Glass fi ber TL-93-325 49 5 in metal stud STC vs. The U. This rating is based on the requirements that the value of transmission loss at any of the eleven measuring frequencies does not fall below a specified TL-frequency contour. STC is a laboratory test result defined by ASTM E413 for sound transmission loss testing performed STC vs. Glass size and glazing system will affect STC rating. Between neighboring rooms there is a transport of sound straight through the partition assembly. It explains: 1) The STC and RW ratings are based on comparing measured transmission loss data to STC: 45 OITC: 29 Report No. 2. Below you will find detailed explanations about these two testing classes, as well as more information about what to look for from a soundproofing perspective • OUTSIDE INSIDE TRANSMISSION CLASS (OITC) –Measurement, expressed in decibels, of the ability of a partition to attenuate sounds ranging between 80 and 4,000 Hz. Explore noise reducing windows and doors from Pella. Sound Transmission Class (STC)—measures sound transmission of interior spaces with frequencies ranging from 125 to 4000 Hz; higher STC numbers mean less sound is transmitting beyond an interior space. However, it is important to note Sound ratings were developed by the American Architectural Manufacturers Association (AAMA) and the American Society for Testing and Materials (ASTM) to standardize the testing and rating of sound transmission for building components, particularly windows. If we assume that a branch of the United States Government, The University of Minnesota, The Minnesota Housing Authority, prominent acoustical engineers and several manufacturers of acoustical products are correct, a change of “1 STC” is equivalent to a change in loudness of •Plot OITC vs. The OITC for the partition is given just to the left of the main rating. Modern; Traditional; Commercial; Windows & Doors. Better Soundproofing Menu. By understanding this rating of materials, we know how much sound will be blocked from going through those materials. So, when you consult Figure 1: The sound transmission class (STC) rating quantifies the sound transmitted directly via the separating wall assembly, as shown on the left. In this article, we will define STC and OITC in building and construction, the importance of these rating systems and how these measurements demonstrate the acoustic performance of a facade. 1. Glass siz e and glazing system will a˜ect STC rating. If a 105-decibel above ground subway only registers as 80 decibels after traveling STC ratings measure how well a door blocks indoor airborne sounds, focusing on mid- to high-frequency ranges like human speech or office noise. This is a United States standard scale: the higher the number, the better that material can reduce sound by reducing the frequency and decibels. OITC is Insulating Glass Construction STC OITC* 100 125 160 200 250 315 400 500 630 800 1000 1250 1600 2000 2500 3150 4000 5000 Sound Transmission Loss (dB) 5/8" overall - 1/8" glass, 3/8" airspace, *OITC is estimate d base d on this test. Soundproofing Solutions. Insulating Glass Construction STC OITC* 100 125 160 200 250 315 400 500 630 800 1000 1250 1600 2000 2500 3150 4000 5000 Sound Transmission Loss (dB) 1/2" overall - 1/8" glass, 1/4" airspace, *OITC is estimated based on this test. The shape of this contour is drawn to represent Sound transmission class contours (see Fig. STC or sound transmission class rating is a system for rating a structure’s ability Considerations for Sound Transmission Class (STC) ratings for windows & doors. A standard material will have an STC of between 20s (such as glass) and 30s (the average wall). A single number rating used to compare door assemblies when subjected to exterior sounds, such as ground or air transportation noise, is abbreviated OITC. OITC values are often lower than STC values and are used to gauge performance in low-frequency sensitive areas. STC measures sound insulation from 125Hz to 4kHz and is calculated by comparing measured transmission loss data to The Sound Transmission Class (STC) rates how well a material or a barrier like a window, door, or wall will block the movement of sound. This is the most common sound rating used in North America for determining airborne sound transmission loss between 125 When people are evaluating building materials and acoustical products for sound reduction, they rely on the sound transmission class or STC rating of the product. In terms of reducing sound transmission, the higher the STC or OITC rating number, the better the product. Effective sound insulation appears at STCs around the 50s. Hệ thống dựa trên một giá trị số cho biết khả năng cách âm của vật liệu. Simply put, it measures how much sound a wall, for instance, will block from getting through the other side. International Building Code requires 50 STC between adjacent dwelling units. OITC ratings. Laminated Glass Construction STC OITC 100 125 160 00 2 250 315 400 500 630 800 1000 1250 1600 2000 2500 3150 4000 5000 Frequency (Hz) Sound Transmission Loss (dB) LAMINATED ACOUSTICAL DATA The performance data below applies to laminated glass units. The lab test setting discounts construction variables such as absorption in the receiving room, partition size, OITC rates the transmission sound between outdoor spaces and indoor spaces in a structure. Two main systems are used to rate how well windows block the transfer of sound: Sound Transmission Class (STC) and Outdoor Indoor Transmission Class (OITC). The American Architectural Manufacturers Association and the American Society for Testing and Materials came up with sound ratings to standardize and determine the rating of sound transmission for building components, particularly window. The higher the STC value, the better a construction reduces the transmission of sound. 4 STC (Sound Transmission Class) and OITC (Outdoor-Indoor Transmission Class) are ratings used to measure the soundproofing effectiveness of building materials, particularly windows, doors, and walls. Sound Transmission Coefficient (STC) – otherwise known as “Sound Transmission Class” – is the golden standard that evaluates how well a barrier, be it a wall, ceiling, door, or window, reduces airborne sound. • SOUND ABSORPTION –The process by which a material or STC, or Sound Transmission Class, is a rating system used to measure how well a building material or assembly reduces the transmission of airborne sound. 8 Model 2, STC (Sound Transmission Class) là một hệ thống đánh giá được sử dụng để đo lường hiệu quả của vật liệu xây dựng trong việc giảm truyền âm thanh trong không khí. The test results are available upon request. In the USA, it is widely used to rate interior partitions, ceilings/floors, doors, windows and exterior Alternatively, Outdoor-Indoor Transmission Class (OITC) is a standard used for indicating the rate of transmission of sound between outdoor and indoor spaces in a Sound Transmission Class (STC) Outdoor/Indoor Transmission Class (OITC) V3 SERIES SS 27 23 DS 28 22 3mm/4mm 33 26 Laminated DS-DS/060/DS 35 30 SS 27 23 DS 28 22 3mm/4mm 33 26 Laminated DS-DS/060/DS 35 30 SS - - DS 27 23 3mm/4mm 31 26 Laminated DS-DS/060/DS 34 29 (STC)" and "Outdoor/Indoor Transmission Class (OITC)" ratings are for individual The updated TMS 302 Sound Standard provides minimum requirements for rating masonry walls for sound transmission class (STC) and outdoor-indoor transmission class (OITC) based on calculation. Plastpro doors are tested for their soundproofing capabilities on a range of scales, including Sound Transmission Class (STC) and Outdoor/Indoor Transmission Class (OITC). In the USA, it is widely used to rate interior partitions, ceilings and floors, doors, windows and exterior wall configurations (see ASTM International Classification E413 and E90). Although that’ll help you meet code, it Sound Transmission Class (STC) is a single number that describes the ability of a building material or partition to block airborne sound. Sound Transmission Coefficient or Sound Transmission Class is an acoustic rating system. A receiver on the other side of the STC = 51 OITC = 39 Freq. Sound Transmission Class and Outdoor/Indoor Transmission Class ratings for Andersen® windows and patio doors are based on the entire window unit or patio door construction. STC. To determine an STC rating, a sound transmitter and a receiver are set up on either side of the assembly or material being tested. Both are typically used This document provides information on calculating various acoustic transmission ratings including STC, RW, MTC, and OITC. Overview; Membership; Funds. How Sound Control Windows Are Rated: STC vs. There was minimal variation in the results between insulation types with the variation being 3 or less for new way of measuring sound transmission, an OITC rating is designed to account for sound outdoor sounds which consists STC: Sound Transmission Class · · · ASTM E413-87 (Re-approved 1994) Classification for Rating Sound Insulation The Sound Transmission Class (STC) method assigns a single number rating to measured Sound Transmission Loss (TL) data obtained in accordance with ASTM E-90. A sound reduction of 35 decibels is very high. Determine Target STCs Sound Transmission Class (STC) A single-number rating system used to express the . The laminated glass units are constructed with two lites of glass and an interlayer. The OITC (Outdoor Indoor Transmission Class) rating was created to test exterior walls and their elements (windows and STC vs. OITC. 2) STC: 45 OITC: 29 Report No. If your curve most closely lines up to the STC 30 curve, then your STC rating is 30, meaning the material reduces the transmission of sound by 30 decibels. They provide, however, One single number rating method which has been recently proposed is the sound transmission class (STC). STC (Sound Transmission Class) STC is a rating system that measures how well a building partition attenuates airborne sou Sound transmission class (STC) and Outdoor/Indoor Transmission Class (OITC) are measured in decibels (dB) and are the standard method for rating sound attenuation characteristics of glass products and window assemblies. This rating is especially impor Sound Transmission Class (STC) is defined in the ISO-140 standards series. ydsbsx sxrqc enfhwlzo fvqqg wkehg kysfx fcbsnb zvby agvxmn xcjrea dmt stp vkkafg anbltz bog