For thermal insulation, acoustic insulation, fire safety and personnel protection
Surface temperature must not exceed 60oC
Noise Reduction Coefficient (NRC) indicates the average sound absorbed by a body. Higher NRC indicate higher absorption. Lower NRC of a material indicates that sound absorbed by it is low. Instead, the material reflects more sound. NRC is an important index to enhance sound quality within a room and reduce echo.
Sound Transmission Class (STC) tells how much sound is blocked from being transmitted by a material. Higher STC rating indicates that more sound is blocked from getting transmitted. Lower STC indicates that sound easily gets transmitted through the material. STC is an important index to enable acoustic privacy and quieter living / working areas. One of the major uses of this index is while designing wall partitions.
Impact Insulation Class (IIC) is used to understand how much of impact noises / vibration is blocked / isolated by the material. It is majorly used in floor and wall assemblies wherein the noise of footsteps and other impact sounds do not get transmitted to the low floors. Higher IIC indicates that the floor is well suited to block the impact noises
Fire safety is assured by criteria detailed in various standards. These criteria normally include combustibility, flame propagation, fire droplets, smoke emission etc. To ensure a product is fire safe, one must look for the standards they adhere to eg : BS 476 Part 4, 6, 7, ASTM E84, UL 723 etc.
EUCEB (European Certification Board for insulation) helps increasing confidence of consumers about the safety of mineral wool products for human health. Any product which is EUCEB certified falls within a specific range of chemical composition measured as per certain testing criteria. These products generally are considered biosoluble and are certified by a third party.
High quality raw material, better thermal performance, stability at high temperatures, low shot content, uniformity in physical properties (such as density, thickness etc.), better fiber quality, lower Chloride content (fewer corrosive impurities), compliance to global standards, acceptability among users and consultants
Thermal conductivity is the ability of a material to transmit heat. It is denoted by ‘k’ or ‘λ’. It is the inherent property of a material and depends on parameters like density, moisture, fiber structure etc. and varies with temperature it is subjected to. It is expressed in W/mK
Thermal resistance indicates the ability of a material to resist transmission of heat. It is denoted by ‘R’ and depends on the dimension (t, through which heat flows) and thermal conductivity. It is calculated as R = t/k and expressed in m2K/W
Shot content is the non-performing, unfiberized material in an insulation. It reduces the insulating properties and only adds to the weight of the material.
Corrosion Under Insulation, also known as CUI, is the corrosion of structures surrounded by insulation material. It is affected by the availability of oxygen, temperature, water and leachable contaminant in insulation. Example of leachable content is Chloride. As chloride content in insulation increases, the rate of material deterioration increases rapidly.
IS 8183
For personal protection
Exposed surface < 60oC
Water absorption
By mass < 0.5Kg/m2 (BS 2972)
ECBC compliant
NCB 2016 (building material, thermal insulation, all buildings)
PEB
Infrastructure building
ECBC complaint
NBC 2016(Duct insulation)
Fire safety for Trains
Interior wall acoustic
STC > 45 dB
Metro coaches
Water absorption < 2%
Vibration and Jolting
Fiber settlement < 3%
Easy installation, less wastage, less joints, better performance, no sagging, good compressive strength, aethetic
The choice of insulation material will depend on many factors namely maximum service temperature, application (flexible, rigid, tensile strength, compressive strength etc.).