Tests
2
Effect of Insulation Flow Resistivity
Rw range
29–31dB
spread 2 dB
Highest Rw
31dB
GW 90 mm R2.7 (34,000 N·s/m⁴)
Largest ΔRw vs first
+4dB
GW 90 mm R2.7 (34,000 N·s/m⁴)
Sound reduction index
R′ from the 2270, re-referenced to the 0.9216 m² specimen area (−0.35 dB). Grey lines: reference bounds.
Single-number ratings
Open in explorer| Varies | Test | Rw | C | Ctr | ΔRw vs first | ΔRw vs open | Mean R | |
|---|---|---|---|---|---|---|---|---|
| GW 90 mm R2.5 (15,000 N·s/m⁴) | Project065 | 29 | −2 | −6 | ref. | +28 | 25.2 | |
| GW 90 mm R2.7 (34,000 N·s/m⁴) | Project067 | 31 | −2 | −6 | +4 | +30 | 28.6 |
Rw, C and Ctr per ISO 717-1 over 100–3150 Hz. ΔRw fits the reference curve to the band-by-band difference curve, which is not the same number as subtracting two separately rounded Rw values. Mean R is the arithmetic mean over the 16 rating bands.