|
Metric
|
Measurement Recommendation
|
|---|
|
Mass – off-line
|
E (coupled with on-line)
|
|
Mass – on-line
|
E
|
|
Size distribution – off line
|
E
|
|
Size distribution – on line
|
E/D
|
|
Surface area – off line
|
O
|
|
Surface area – on line
|
O
|
|
Number – off line
|
N
|
|
Number – on line
|
E
|
- E: These measurements are considered to be essential.
- D: These measurements are considered to provide valuable information, but are not recommended as essential due to constraints associated with complexity, cost and availability.
- O: These measurements are considered to provide valuable but non-essential exposure information.
- N: These measurements are not considered to be of significant value to inhalation studies.
