Group-specific requirements

Silencers

These requirements refer to silencers intended to be used mainly in public, commercial, office or residential buildings. Classified silencers must fulfil the requirements specified in the Finnish Code of Building Regulations (fire protection, sound insulating), and their silencing properties must be documented.

The products must fulfil the general requirements specified in section 3.2.2.1 of the Classification of Indoor Climate 2000. These requirements are presented in section Requirements for classification.

Tests and requirements for silencers

• Fibre release test (required)
  The silencer must not release a harmful amount of fibres into the air flow under any circumstances. The silencers go through a vibration test and a brushing test as specified in Appendix 7.
  
  Classification criteria:
  When measured using a filtering method, the maximum amount of mineral fibres (over 20 µm long) is:
  • 10 fibres/m3 in the vibration test
  • 0.1 fibres/m3 in the 24 h test after the brushing.
    
    Appendix 7 Determining the number of mineral fibres released into the air flow




• Sensory tests (optional)
  The quality of the air flowing through the silencer must be acceptable.
  If necessary, odour emission is to be determined as specified in appendices 1 or 6, or using the sensory tests specified for the emission classification of building materials (Emission Classification of Building Materials).
  
  Appendix 1 Sensory assessment with a trained panel
  Appendix 6 Sensory assessment with an untrained panel

• Special requirements on production information
  The acoustic properties, instructions for use and cleaning, nominal air flow and possible use restrictions of silencers must be made available both together with the product and separately.
  
  The perforated sheet metal or other material used in the silencer fulfils the requirements for processes requiring oil, 0.3 g/m2 (300 mg). The certificate must be attached to the application.

• Cleaning needs of silencers
  The manufacturer must specify the cleaning needs of the silencer and the way in which used silencers can be disposed of in an environmentally friendly manner.