Particle mater in room air limits are in particles of 0.5 μm and larger per cubic meter.
ISO = cubic
meter (m3)
FD Standard 209 E = cubic feet
(ft3)
ISO class equal
to federal standard 209 E class .
1m3 = 35.31 ft3
1m = 100 cm
Adapted from former Federal
Standard No. 209 E,
ISO = international organization for standard 14644
part -1, may -1999 published.
Maximum concentration limits (particles M3 of air) for
particles equal to and larger than the considered sizes shown below: (a)
|
||||||||||
ISO Classification Number(N)
|
0.1µm
|
0.2µm
|
0.3µm
|
0.5µm
|
1.0µm
|
5.0µm
|
||||
ISO 1
|
b
10
|
d
|
d
|
d
|
e
|
|||||
ISO 2
|
100
|
24
|
10
|
d
|
e
|
|||||
ISO 3
|
1,000
|
237
|
102
|
35
|
e
|
|||||
ISO 4
|
10,000
|
2,370
|
1,020
|
352
|
83
|
e
|
||||
ISO 5
|
100,000
|
23,700
|
10,200
|
3,520
|
832
|
|||||
ISO 6
|
1,000,000
|
237,000
|
102,000
|
35,200
|
8,320
|
293
|
||||
ISO 7
|
c
|
c
|
c
|
352,000
|
83,200
|
2,930
|
||||
ISO 8
|
c
|
c
|
c
|
3,520,000
|
832,000
|
29,300
|
||||
ISO 9
|
c
|
c
|
c
|
35,200,000
|
8,320,000
|
293,000
|
||||
5.0µm should be zero according to ISO/DIS 14644-1.2 Table
1 notes;
d) Sampling and statistical limitations for particles in
low concentrations make classification inappropriate
e) ... Greater than 1 micron particles make classification
at this particle size inappropriate due to potential particle losses in sampling
system
f) Specify particle size in association with ISO Class 5,
the marcoparticle discriptor M may be adapted.
 |
||||||||||
Maximum permitted number of particles per
m3 equal to or greater than the tabulated size
|
||||||||||
Grade
|
At
Rest
|
In
Operation
|
||||||||
0.5µm
|
5.0µm
|
0.5µm
|
5.0µm
|
|||||||
A
|
3,520
|
20
|
3,520
|
20
|
||||||
B
|
3,520
|
29
|
352,000
|
2.900
|
||||||
C
|
352,000
|
2.900
|
3.520.00
|
29.000
|
||||||
D
|
3,520,000
|
29.000
|
Not Defined
|
Not Defined
|
||||||
