Basic Documentation

Room Pressurization Control Application Guide
Table 2 provides the allowable limits for 0.1, 0.5 and 5.0 micron size airborne particles per
cubic foot and cubic meter for different clean room classifications for the current versions of
the FS 209E and ISO/FDIS 14644-1 standards. These standards also establish allowable
limits for other size particles aside from those listed in the table, however the particle sizes
listed in Table 2 provide a comparison between the two standards.
Table 2. Clean Room Standards—Particle Concentration Limits FS 209E vs. ISO 14644-1.
0.1 µm Particles Per
Cubic Unit
0.5 µm Particles Per
Cubic Unit
5.0 µm Particles Per
Cubic Unit
Clean Room
Classification
FS ISO FS ISO FS ISO
FS ISO Cubic
Ft.
Cubic
Meter
Cubic
Meter
Cubic
Ft.
Cubic
Meter
Cubic
Meter
Cubic
Ft.
Cubic
Meter
Cubic
Meter
1
10
2
100 4
1 M1.
5
3
35 1,230 1,000 1 35 32
10 M2.
5
4
345 12,200 10,000 10 353 352
100 M3.
5
5
3,450 122,000 100,000 100 3,530 3,520 29
1,000 M4.
5
6
34,500 1,220,0
00
1,000,0
00
1,000 35,300 35,200 7 247 293
10,000 M5.
5
7
345,000 1.22 ×
10
7
10,000 353,000 352,000 65 2,300 2,930
100,00
0
M6.
5
8
3,450,0
00
1.22 ×
10
8
100,00
0
3,530,0
00
3,520,00
0
700 24,700 29,300
9
3.45 ×
10
7
1.22 ×
10
9
35,200,0
00
293,00
0
32 Siemens Building Technologies, Inc.