Natural strength

Ceiling and wall cladding in sports facilities and gymnasiums are exposed to stress from ball impacts.

In Germany, documentation is required for the ‘certification to withstand ball impact’ of the materials in accordance with ‘Prüfung der Ballwurfsicherheit, DIN 18032 Teil 3, Sportshallen für Turnen und Spiele’ (requirements and testing of ball impact safety, DIN 18032, Part 3, sports facilities). The tests are carried out at a laboratory in the facility for research and materials testing for the construction industry (Forschungs- und Materialprüfungsanstalt für das Bauwesen (FMPA)) at the Otto-Graf Institute at the University of Stuttgart. The CE standard for suspended ceilings, EN 13964, also includes ball impact certification as a parameter, and the German tests are performed accordingly. In accordance with EN 13964, Annex D, Impact resistance, Troldtekt is classified as class 1A.

A wide range of structures fitted with Troldtekt acoustic panels have been tested at the institute in Stuttgart and have been approved for use as ceiling and wall cladding in sports facilities. This applies to structures on wooden battens as well as structures suspended in C60 profile systems.

Prüfung der Ballwurfsicherheit DIN 18032, Teil 3, Sportshallen für Turnen und Spiele / EN 13964, Annex D, Impact resistance.

Ceiling cladding

A handball is thrown 36 times against the test ceiling at a velocity of 16.5 ± 0.8 m/s. The shots are thrown 2 × 12 times at an angle of 60° and 1 × 12 times at an angle of 90°.

Wall cladding

A handball is thrown 54 times against the test wall at a velocity of 22.5 ± 1.2 m/s. The shots are thrown 2 × 12 times at an angle of 45° and 1 × 30 times at an angle of 90°.

When planning indoor shooting ranges, special requirements pursuant to the Shooting Range Regulations of the Federal Ministry of the Interior (BMI) (of 23 July 2013, first amendment of 13 March 2013) must be observed in regard to the sound absorption and fire protection. In addition, precautions must be taken against ricocheting and rebounding projectiles or projectile parts when designing indoor shooting ranges.

Sound absorption

Behind the firing line, the walls and ceiling of the shooting range must be covered with sound-absorbing material, depending on the precise use, as residents and other persons must not be affected by the shooting noise (up to 160 dB).

Indoor shooting ranges are facilities in accordance with section 3(5) of the German Federal Immission Control Act (BImSchG) and are subject to the requirements of section 22 of that act. The permissible immission reference values of the Technical Instructions for Protection against Noise (TA Lärm) must be observed.

For the selection of sound-absorbing materials within the shooting range: the mean reverberation time should not exceed the required value of T60 < 0.5 s over the frequency range from 125 to 4000 Hz. The mean sound absorption level should not be less than the required value of αs > 0.5 at the octave average/mean frequency of f = 500 Hz, which is relevant for shooting noise.

Fire protection

It must be ensured that the wall and ceiling materials used do not drip or develop toxic gases in the event of a fire. The sound-absorbing wall and ceiling coverings used in indoor shooting ranges must be at least flame retardant according to building material class B 1 in accordance with DIN 4102, Part 1. According to DIN EN 13501-1, at a minimum the criteria C, s1 and d0 must be met.

Ricochet protection for ceilings and walls

The cladding must be smooth and ricochet-proof. The following safety requirements for the materials to be used must be ensured:

Impacting projectiles must be safely absorbed at a hit angle between 25 degrees and 60 degrees. Projectiles or parts thereof may not ricochet back from the surface towards the shooting positions; the visible material surface must be flat and resistant to abrasion and mechanical stress. Test confirmations or certificates for the resistance of the material used against ricochet and rebound must be available.