APPENDIX D Surface Absorption Coefficients _ for Various Materialsa

Back

Material

Octave band center frequency, Hz

125 250 500 1,000 2,000 4,000

Walls and ceilings:

Brick, unglazed 0.03 0.03 0.03 0.04 0.05 0.07

Brick, unglazed and painted 0.01 0.01 0.02 0.02 0.02 0.03

Concrete block, unpainted 0.36 0.44 0.31 0.29 0.39 0.25

Concrete block, painted 0.10 0.05 0.06 0.07 0.09 0.08

Door, solid wood panel 0.10 0.07 0.05 0.04 0.04 0.04

Marble or terrazzo 0.01 0.01 0.015 0.02 0.02 0.02

Plaster, gypsum or lime,

on tile/brick

0.013 0.015 0.02 0.03 0.04 0.05

Plaster, smooth finish on lath 0.14 0.10 0.06 0.04 0.04 0.03

Plaster, fibrous 0.35 0.30 0.20 0.15 0.10 0.04

Plaster, on wood wool 0.40 0.30 0.20 0.15 0.10 0.10

Poured concrete, unpainted 0.01 0.01 0.02 0.02 0.02 0.03

Poured concrete, painted 0.01 0.01 0.01 0.02 0.02 0.02

Sprayed-on cellulose fibers:

5

8-inch thick on solid backing 0.05 0.16 0.44 0.79 0.90 0.91

1-in thick on solid backing 0.08 0.29 0.75 0.98 0.93 0.76

1-in thick on metal lath with

air space

0.47 0.90 0.99 0.99 0.99 0.99

Copyright © 2003 Marcel Dekker, Inc.

Surface Absorption Coefficients 511

Material

Octave band center frequency, Hz

125 250 500 1,000 2,000 4,000

Open-cell polyurethane foam:

11

2-in thick 0.05 0.16 0.66 0.99 0.99 0.92

13

4-in thick 0.10 0.25 0.52 0.89 0.99 0.95

2-in thick 0.16 0.25 0.57 0.82 0.86 0.86

21

4-in thick 0.23 0.41 0.75 0.93 0.85 0.77

Fiberglass formboard:

1-in thick 0.18 0.34 0.79 0.99 0.93 0.90

11

2-in thick 0.25 0.49 0.98 0.99 0.91 0.85

2-in thick 0.33 0.67 0.99 0.99 0.94 0.90

Ceiling board, fiberglass cloth faced:

1-in linear 0.07 0.24 0.66 0.95 0.99 0.95

1-in nubby surface 0.06 0.25 0.68 0.97 0.99 0.92

1-in textured surface 0.10 0.27 0.75 0.99 0.99 0.84

Plywood panels:

1

8-in with 11

4-in air space 0.15 0.25 0.12 0.08 0.08 0.08

1

8-in with 21

4-in air space 0.28 0.20 0.10 0.10 0.08 0.08

3

16-in with 2-in air space 0.38 0.24 0.17 0.10 0.08 0.05

3

16-in with 2-in air space filled 0.42 0.36 0.19 0.10 0.08 0.05

with fibrous insulation

1

4-in with small air space 0.30 0.25 0.15 0.10 0.10 0.10

3

4-in with small air space 0.20 0.18 0.15 0.12 0.10 0.10

Plywood panelling, 3

8-in 0.28 0.22 0.17 0.09 0.10 0.11

Gypsum board, 11

2-in on studs 0.29 0.10 0.06 0.05 0.04 0.04

Sound-absorbing masonry blocks:

4-in thick, unpainted, 2

unfilled cavities

0.19 0.83 0.41 0.38 0.42 0.40

4-in, painted, 2 insulationfilled

cavities

0.20 0.88 0.63 0.65 0.52 0.43

6-in, painted, 2 unfilled

cavities

0.62 0.84 0.36 0.43 0.27 0.50

6-in, painted, 2 insulationfilled

cavities

0.39 0.99 0.65 0.58 0.43 0.45

8-in, painted, 2 unfilled

cavities

0.97 0.44 0.38 0.39 0.50 0.60

8-in, painted, 2 insulationfilled

cavities

0.33 0.94 0.62 0.60 0.57 0.49

8-in, painted, 3 insulationfilled

cavities

0.61 0.91 0.65 0.65 0.42 0.49

Perforated acoustic ceiling tile:

1

2-in thick, hard backing 0.08 0.17 0.55 0.73 0.72 0.67

3

4-in thick, hard backing 0.10 0.22 0.72 0.88 0.75 0.66

Copyright © 2003 Marcel Dekker, Inc.

512 Appendix D

Material

Octave band center frequency, Hz

125 250 500 1,000 2,000 4,000

1-in thick, hard backing 0.12 0.31 0.93 0.90 0.72 0.63

3

4-in, furring backing 0.12 0.42 0.71 0.88 0.75 0.65

3

4-in, mech. suspension 0.30 0.51 0.80 0.85 0.78 0.66

Acoustic foam:

1

4-in thick 0.08 0.10 0.20 0.30 0.60 0.93

1

2-in thick 0.12 0.21 0.36 0.54 0.92 0.98

3

4-in thick 0.14 0.25 0.44 0.70 0.98 0.99

1-in thick 0.16 0.28 0.51 0.78 0.99 0.99

2-in thick 0.27 0.48 0.80 0.99 0.99 0.99

Ventilating grille 0.30 0.40 0.50 0.50 0.50 0.50

Floors:

Carpet:

44 oz 1

4-in thick wool

woven pile, uncoated

backing, on 40 oz hair

pad

0.17 0.35 0.66 0.71 0.70 0.65

44 oz 1

4-in thick wool

woven pile, coated

backing, on 40 oz pad

0.17 0.35 0.46 0.36 0.40 0.45

3

8-in thick wool pile on

concrete; no pad

0.09 0.08 0.21 0.26 0.27 0.37

5

8-in thick wool pile, with

pad

0.20 0.25 0.35 0.40 0.50 0.75

Indoor–outdoor carpet 0.01 0.05 0.10 0.20 0.45 0.65

Linoleum/rubber tile on

concrete

0.02 0.03 0.03 0.03 0.03 0.02

Varnished wood joist floor 0.15 0.11 0.10 0.07 0.06 0.07

Windows:

Large panes, plate glass 0.18 0.06 0.04 0.03 0.02 0.02

Small panes, ordinary glass 0.04 0.04 0.03 0.03 0.02 0.02

Draperies:

Cotton fabric, draped to half

area, 14 oz/yd2

0.07 0.31 0.49 0.81 0.66 0.54

Velour, straight, 10 oz/yd2 0.04 0.05 0.11 0.18 0.30 0.35

Velour, straight, 14 oz/yd2 0.05 0.07 0.13 0.22 0.32 0.35

Velour, straight, 18 oz/yd2 0.05 0.12 0.35 0.48 0.38 0.36

APPENDIX D (Continued)

Copyright © 2003 Marcel Dekker, Inc.

Surface Absorption Coefficients 513

Material

Octave band center frequency, Hz

125 250 500 1,000 2,000 4,000

Velour, draped to half area,

14 oz/yd2

0.07 0.31 0.49 0.75 0.70 0.60

Velour, draped to half area,

18 oz/yd2

0.14 0.35 0.53 0.75 0.70 0.60

Natural outdoor materials:

Grass, 2 in high 0.11 0.26 0.60 0.69 0.92 0.99

Gravel soil, loose and moist 0.25 0.60 0.65 0.70 0.75 0.80

Snow, 4 in deep 0.45 0.75 0.90 0.95 0.95 0.95

Water surface 0.01 0.01 0.01 0.02 0.02 0.03

People and furniture: Values of р_SЮ, m2 per person or item

Person in upholstered chair 0.30 0.315 0.35 0.42 0.42 0.39

Upholstered chair, empty 0.23 0.26 0.30 0.325 0.325 0.30

Person in wood theater seat 0.23 0.28 0.325 0.35 0.37 0.35

Wood theater seat, empty 0.01 0.02 0.02 0.03 0.04 0.04

Adult or high school

student in desk

0.20 0.28 0.31 0.37 0.41 0.42

Child or elementary school

student in desk

0.17 0.21 0.26 0.30 0.325 0.37

Empty desk 0.10 0.13 0.14 0.17 0.18 0.15

Person standing 0.19 0.325 0.44 0.42 0.46 0.37

aThe values have been selected from manufacturer’s catalog data.

Copyright © 2003 Marcel Dekker, Inc.

Навигация