Drug powders are classified by their behavior in standard sieves.
|
Classification |
Vegetable and Animal Drugs |
|
very coarse |
all particles pass through a No. 8 sieve; no more than 20% pass through a No. 60 sieve ("No. 8") |
|
coarse |
all particles pass through a No. 20 sieve; no more than 40% pass through a No. 60 sieve ("No. 20") |
|
moderately coarse |
all particles pass through a No. 40 sieve; no more than 40% pass through a No. 80 sieve ("No. 40") |
|
fine |
all particles pass through a No. 60 sieve; no more than 40% pass through a No. 100 sieve ("No. 60") |
|
very fine |
all particles pass through a No. 80 sieve ("No. 80") |
|
Sieve |
VC |
coarse |
MC |
fine |
VF |
|
No. 8 |
100% |
|
|
|
|
|
No. 20 |
|
100% |
|
|
|
|
No. 40 |
|
|
100% |
|
|
|
No. 60 |
<= 20% |
<= 40% |
|
100% |
|
|
No. 80 |
|
|
<= 40% |
|
100% |
|
No. 100 |
|
|
|
<= 40% |
|
|
Classification |
Chemicals |
|
very coarse |
not defined |
|
coarse |
all particles pass through a No. 20 sieve; no more than 60% pass through a No. 40 sieve ("No. 20") |
|
moderately coarse |
all particles pass through a No. 40 sieve; no more than 60% pass through a No. 60 sieve ("No. 40") |
|
fine |
all particles pass through a No. 80 sieve ("No. 80") |
|
very fine |
all particles pass through a No. 120 sieve ("No. 120") |
|
Sieve |
coarse |
MC |
fine |
VF |
|
No. 20 |
100% |
|
|
|
|
No. 40 |
<= 60% |
100% |
|
|
|
No. 60 |
|
<= 60% |
|
|
|
No. 80 |
|
|
100% |
|
|
No. 100 |
|
|
|
|
|
No. 120 |
|
|
|
100% |
In the implementation:
• I used very coarse for chemical powder since I didn't have any better term to use.
• For powders defined by no more than X% pass through a sieve, I classified these as "plus").
