Fed Std
209D
(1988)

Fed Std
209E
(1992)

EU
CGMP
(1998)

EN ISO
14644-1
(1999)

1

M1.5

ISO 3

10

M2.5

ISO 4

100

M3.5

A, B

ISO 5

1,000

M4.5

ISO 6

10,000

M5.5

C

ISO 7

100,000

M6.5

D

ISO 8