Be aware that the VMD regulations do not permit pure OA to be used to treat varroa and that you will be in breach of the law if you do so.
The reason for this is that although OA had been used successfully for many years without regulation, a commercial product developed by Chemicals Laif called ApiBioxal was regulated by the VMD more recently at great cost. To reduce risk of dosing variability (and give commercial advantage) pure OA was outlawed.
What is so different between OA and ApiBioxal? In OA terms, nothing, but AB has silica added to prevent solidification in storage, and sugar for no particular reason. These two additives will caralemise in your sublimator and cause much cursing and scraping,
The big however is that many beekeepers continue to use OA in full knowledge (or ignorance of the law) that it does the same job more efficiently at vastly reduced cost, and are also confident that the VMD is highly unlikely to spend on a test case and prosecute a beekeeper for using a forbidden product.
The description in your link takes account of the regs. and states that it c
an be used as a hive cleaning agent, and indeed it is used commonly for cleaning wood.
The linked mask has a filter graded P3 which is the highest particulate level, but it has no A filter to deal with sublimated OA.
Filter coding: P is for particulate filters and A is for organic vapour filters. More homework needed: read again the thread linked earlier, esp. the
info. guide and link to the
Types & Classes of Gas Filters and
Particulate Filter Protection Levels. Some makes have their own interpretation of the codes, but you can cross-reference until you arrive at A and P classes to grade 2 as a minimum.
The mask must also protect eyes, which have a liquid surface that will absorb sublimated OA, but you could use PPE glasses with fully sealing rims.