No effect on the track decay rate
The Calmmoon Rail web shielding has a weight of about 4 kg per linear metre of rail. The Calmmoon Rail technology does not affect the vibration of the rail and thus does not affect the decay rate of the track.
Connection between track decay rate and noise reduction potential
Classic mass spring systems increase the decay rate of the track and reduce the emitted rail noise in this way. To do this, about 25 kg mass is installed per linear metre of rail.
For track with a very good decay rate, the effect of mass spring systems is reduced accordingly. This can be seen clearly from the diagram "Relationship of track decay rate versus noise reduction".
Good rail - high track decay rate
Calmmoon Rail technology has demonstrated in several field measurements that even for high decay rates of the rails, e.g. 8 dB/m in the range of 500 - 2,000 Hz according to TSI, a noise reduction of the overall noise level of 2 to 4.4 dB is achieved depending on the type of train. In these cases, the rail roughness was always lower than that specified by TSI and ISO standards.
If you check the decay rate of 8 dB/m in the diagram "Relationship of track decay rate versus noise reduction" you will see that the possible noise reduction of mass spring systems is in the range of 1.0 to 1.5 dB.