Exploration and exploitation of acoustic shielding materials 28. 07. 2011 Lukáš Černý Exploration and exploitation of acoustic shielding materials Supervisor Prof. Dr. Ali H. Reshak

Environment and health Environmental protection program of developted countries: 1. Air pollution 2. Water pollution 3. Acustic pressure High noise for long time can couse: 1. Specific disturbancs Deafness 2. Non-specific disturbancs Psychical problems Low Performance

What we can hear Ear translates frequency into nerve impulses Low frequency under 16 - 20Hz infrasound High frequency over 20 KHz ultrasound

Shielding materials

Shielding materials - types Absorbing Diffusing Bass trap

Ear Protection Reduce noise Changing filtres Individually use Excellent sound

Measure value

results Background 34 dB Noise level 45,5 dB Day limit 50dB 6am – 10 pm Night limit 40dB 10pm – 6am Reduce noise 5,5dB till 125Hz

acknoledgments Thanks to: Supervisor prof. Dr. Ali H. Reshak My colleagues for support Summer school for opportunity Sponsor