Before you begin for the first time you will need to drill a 1/4" hole in the bottom board centered in the 3/4" strip of wood between the bottom & the hive body. Plug the entrance and any vents with a rag & put your barriers in place for screen bottoms. You want it to be as airtight as possible to minimize your exposure to the vapors. Note any leaks when you do the hive for the first time and try to see where you can seal it better in the future. Always, before you start, stick a 1/4" rod or a #2 phillips head screw driver in the holes of all the hives you're treating to make sure the bees haven't built any burr comb that would obstruct the flow or possibly plug the vaporizer.
Ok, plug in the MiteBlaster and let it heat up to 210C. Now place 1 gram or 1/4 teaspoon of oxalic acid per brood chamber into the cup. Place the cup next to the reaction chamber and just flip it over onto the top, then tap on the top to make sure the OA drops down. The silicone cup swells up a little and seals nicely so don't mash down on it. If you press it in too hard it will be difficult to remove. Its all vaporized in under 10 seconds, but I usually leave it in the hive while I clean and load the cup for the next hive to minimize exposure to vapors. When your finished, move the MiteBlaster to the next hive, then remove the used cup with one hand and put the freshly loaded cup on with the other, again to minimize vapor exposure. Don't rush, if you go too fast you may have to pause to let the heater catch up. Just make sure its set to 210C when you start and the temperature is above 200C before you use it, also, check for obstructions before and during use. I little smoke will come out the end of the pipe between hives and thats sufficient proof. Alway use adequate eye and lung protection. I wear an organic vapor cartridge type respirator and always try to work the hives where I stay upwind as much as possible just in case the mask were to leak.
When your done unplug the MiteBlaster, make sure you take the last cup off, leave it on top of the last hive you did and get away from there for a while till it cools off and quits smoking. After it cools run hot water through the reaction chamber and out of the 1/4” tube to flush out any residual OA to prevent corrosion during storage. Leave the hives sealed up for at least 15 minutes after treatment to allow the OA to settle.
Oxalic Acid Vaporization is a very safe and effective method of varroa mite treatment in any type of honeybee colony when done correctly.