Tests
2
Effect of Insulation Flow Resistivity
Rw range
14–19dB
spread 5 dB
Highest Rw
19dB
GW 90 mm R2.7 (34,000 N·s/m⁴)
Largest ΔRw vs first
+8dB
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) | Project064 | 14 | 0 | −3 | ref. | +14 | 13.1 | |
| GW 90 mm R2.7 (34,000 N·s/m⁴) | Project068 | 19 | −1 | −3 | +8 | +19 | 19.2 |
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.