Name: Fiberglass duct liner with surface coating
Creator: Physikalisch-Technische Bundesanstalt (PTB)
License: https://acousticindex.com/en/terms-of-use

Measured values as a table (18 measurements)

Fiberglass duct liner with surface coating: sound absorption coefficient αs per ISO 354 by frequency and test build-up
Build-up	α_w	125 Hz	250 Hz	500 Hz	1000 Hz	2000 Hz	4000 Hz
1 inch · 0.12 lb/ft² · 25 mm	0.55	0.34	0.42	0.47	0.84	0.80	0.79
1 1/2 inch · 0.18 lb/ft² · 25 mm	0.75	0.29	0.55	0.72	0.85	0.89	0.89
2 inches · 0.24 lb/ft² · 25 mm	0.90	0.32	0.71	0.83	0.91	0.95	1.01
1 inch · 0.17 lb/ft² · 25 mm	0.65	0.23	0.47	0.57	0.74	0.85	0.87
1 1/2 inch · 0.25 lb/ft² · 25 mm	0.80	0.33	0.57	0.79	0.91	0.92	0.89
2 inches · 0.34 lb/ft² · 25 mm	0.95	0.39	0.69	0.92	0.98	0.93	1.00
1 inch · 0.25 lb/ft² · 25 mm	0.65	0.23	0.47	0.61	0.79	0.88	0.91
1 1/2 inch · 0.37 lb/ft² · 25 mm	0.85	0.37	0.63	0.80	0.90	0.89	0.90
2 inches · 0.5 lb/ft² · 25 mm	1.00	0.36	0.79	0.96	0.99	0.93	0.97
1 inch · 0.12 lb/ft² · 0	0.55	0.10	0.28	0.50	0.70	0.82	0.83
1 1/2 inch · 0.18 lb/ft² · 0	0.70	0.20	0.40	0.71	0.86	0.91	0.85
2 inches · 0.24 lb/ft² · 0	0.80	0.22	0.49	0.83	0.89	0.89	0.91
1 inch · 0.17 lb/ft² · 0	0.60	0.10	0.29	0.59	0.72	0.83	0.84
1 1/2 inch · 0.25 lb/ft² · 0	0.70	0.20	0.42	0.80	0.93	0.93	0.88
2 inches · 0.34 lb/ft² · 0	0.85	0.24	0.57	0.90	0.95	0.95	0.96
1 inch · 0.25 lb/ft² · 0	0.55	0.05	0.25	0.57	0.78	0.87	0.89
1 1/2 inch · 0.37 lb/ft² · 0	0.75	0.20	0.46	0.82	0.94	0.95	0.91
2 inches · 0.50 lb/ft² · 0	0.95	0.27	0.72	1.04	1.02	0.96	0.92

Data source

PTB reference data

Fiberglass duct liner with surface coating

Material properties

Measurement data

Sound absorption

Frequency values

			Value
2 inches	0.5 lb/ft²	25 mm	α_w1.00
2 inches	0.34 lb/ft²	25 mm	α_w0.95
2 inches	0.50 lb/ft²	0	α_w0.95
2 inches	0.24 lb/ft²	25 mm	α_w0.90
1 1/2 inch	0.37 lb/ft²	25 mm	α_w0.85
2 inches	0.34 lb/ft²	0	α_w0.85
1 1/2 inch	0.25 lb/ft²	25 mm	α_w0.80
2 inches	0.24 lb/ft²	0	α_w0.80
1 1/2 inch	0.18 lb/ft²	25 mm	α_w0.75
1 1/2 inch	0.37 lb/ft²	0	α_w0.75
1 1/2 inch	0.18 lb/ft²	0	α_w0.70
1 1/2 inch	0.25 lb/ft²	0	α_w0.70
1 inch	0.17 lb/ft²	25 mm	α_w0.65
1 inch	0.25 lb/ft²	25 mm	α_w0.65
1 inch	0.17 lb/ft²	0	α_w0.60
1 inch	0.12 lb/ft²	25 mm	α_w0.55
1 inch	0.12 lb/ft²	0	α_w0.55
1 inch	0.25 lb/ft²	0	α_w0.55