Mineral woolHighly absorbent
Data source
PTB reference data
Physikalisch-Technische Bundesanstalt
Source: C.M.Harris, Noise Control in Buildings, McGraw Hill 1994
Value from the PTB table, not verified
Armstrong Type 823 fissured mineral fiber, fire-resistant lay-in panel
Type 823
PTB reference data
Original description
Armstrong Type 823 fissured mineral fiber, fire-resistant lay-in panel
Material properties
Manufacturer: Armstrong World Industries
Thickness: 5/8 inch
Wall distance: 16 in
Up to fire class: fire-resistant
Measurement data
Sound absorption
Reverberation chamber (ASTM C423 / ISO 354)· 2 variants
NRC
0.60
Frequency values
αp per octave band
| f (Hz) | 125 | 250 | 500 | 1k | 2k | 4k |
|---|---|---|---|---|---|---|
| αp | 0.35 | 0.35 | 0.50 | 0.80 | 0.85 | 0.85 |
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| Compare | Value | |
|---|---|---|
| 1.0 lb/ft² | NRC0.60 | |
| 1.15 lb/ft² | NRC0.60 |
NRC: 0.60 (derived from ISO 354 lab data)
Dimensions: 24 x 48 inches
Distance: 16 in
Measured values as a table (2 measurements)
| Build-up | NRC | 125 Hz | 250 Hz | 500 Hz | 1000 Hz | 2000 Hz | 4000 Hz |
|---|---|---|---|---|---|---|---|
| 5/8 inches · 1.0 lb/ft² · 400 mm | 0.60 | 0.33 | 0.36 | 0.50 | 0.78 | 0.84 | 0.84 |
| 5/8 inches · 1.15 lb/ft² · 400 mm | 0.60 | 0.35 | 0.34 | 0.48 | 0.69 | 0.88 | 0.92 |
Measured values as a table (2 measurements)
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