Mask tested | Testing condition | |
0.25 µm | 0.5 µm | |
Foreign-manufactured | ||
Batch 1 | Not tested* | Passed |
Batch 2 | Failed | Failed |
Batch 3 | Passed | Passed |
US-manufactured | Passed | Not tested |
The US-manufactured mask successfully filtered out particles of 0.25 µm. Of the three batches of the foreign-manufactured masks, batch #2 failed to filter out 0.25 µm and 0.5 µm particles.
*Note that 0.25 µm microspheres were not tested in batch #1 since we used up our available supply at the time.