Sound Isolation
Safety Doors must provide thermal insulation between its two way sides. Sound isolation is a type of insulation to reduce the negative effects of rumble. Controlling the spread of the Sounds in the environment to is the primary purposes of sound insulation. Sound acts such the other physical phenomenas when face an obstacle while spreading in the environment. Namely, some portion of sound reflected back as some absorbed by the obstacle but some portion passes through the obstacle. So every material has its own max potantial of insulation for Sound.
