REDUCTION OF IMPACT SOUND PRESSURE LEVEL (ISO 16251-1)

A Fast and Cost-Effective Method

The ISO 16251-1 standard describes a method for determining the reduction in impact sound pressure level, ΔLw, of lightweight floor coverings using a test specimen of only 1 m². The results correlate well with those obtained using the reverberation room method described in ISO 10140-3, which requires a 10 m² specimen. The ΔLw values typically differ by no more than 2 dB from those measured according to ISO 10140-3*.

The method is based on a test rig (Figure 1) consisting of a 400 kg concrete slab mounted on springs. The slab is excited using a standardized tapping machine. The vibration velocity of the slab is directly related to the amount of airborne sound it would radiate into the room below. The test involves measuring the vibration velocity of the slab both without and with the floor covering sample. The difference in vibration levels corresponds to the reduction in impact sound pressure level, ΔL, expressed in decibels. The measurement is conducted over the frequency range 100–3150 Hz.

Results and Their Application

The test results include the frequency-dependent reduction in impact sound pressure level, ΔL, in one-third octave bands (Figure 2), and the weighted reduction in impact sound pressure level, ΔLw. The ΔLw value indicates how much the floor covering reduces the weighted impact sound pressure level, Ln,w, of the bare floor.

Applicable Floor Coverings

This method is intended exclusively for lightweight floor coverings, such as:

  • Parquet and laminate flooring with underlay
  • Vinyl and other glued floor coverings
  • Textile carpets

Sample Size

A test specimen of 1200 × 800 mm is required.

Figure 1. Concrete test rig with a floor covering installed. The tapping machine used to generate the test signal is placed on top of the slab.

 

Figure 2. (a) Frequency-dependent reduction in impact sound pressure level, ΔL, for a specific floor covering. (b) The impact sound pressure level of the bare floor is reduced by ΔL when the floor covering shown in (a) is applied.

Research reference

* Keränen J, Lietzén J, Kylliäinen M, Hongisto V (2013). Improvement of impact sound reduction by floor coverings – measurements using a small floor mock-up and an impact sound laboratory, paper 530, Internoise 2013, 15-18 September, Innsbrück, Austria.

 

Delivery and Location

The laboratory is located at Joukahaisenkatu 7, 20520 Turku. Instructions for deliveries can be found here.