Guys, you're missing the point when it comes to diffusing "Essential Oils" around your birds...When it comes to diffusing "Essential-Oils" around your birds, the main thing that you need to be aware of and do lots and lots of research on is NOT the brand of Essential-Oil you're using, or even so-much what "grade" the Oil you choose is, but rather WHAT ESSENTIAL OIL YOU'RE USING IS, AND WHETHER OR NOT IT'S TOXIC/POISONOUS FOR BIRDS TO BREATHE-IN!
***There are literally hundreds of different, what do you call them, "scents" or "flavors", lol, of Essential Oils that you can buy to diffuse into the air. And that's what matters, exactly which Essential-Oils you choose to diffuse/burn around your birds, because I'd guess as high as 95% or more of Essential Oil varieties are completely toxic/poisonous for birds to breathe-in! We also need to remember that not all types of wood/branches are safe to make perches/stands/toys out of for your birds...So that in and of itself rules-out a ton of varieties of Essential Oils. The entire reason that you cannot make toys/perches/stands for your birds out of certain types of wood such as Pine, Cedar, Redwood, etc. (there are a lot) is due to the OIL that these specific woods contain which are poisonous/toxic to birds for one reason or another. So just like birds cannot tolerate breathing-in/inhaling/smelling or touching/having physical contact with certain "scents", you always have to consider the SOURCE of those scents, which are typically plants, trees, the fruits of plants and trees, etc. And these are the exact same sources that Essential Oils are made from, and of course that includes the "all-natural" or "Therapeutic Grade" Essential Oils as well.
***The general rule, if you ask any Certified Avian Vet/Avian Specialist Vet, as well as any Ornithologist, is that you should not diffuse/burn anything in the presence of birds that emits either a scent or an oil/smoke/vapor into the air. Of course that would include ALL Essential Oils, just as it includes ALL candles (yes, soy candles too, again it has nothing to do with whether the candle is regular wax or natural soy wax, it's the SCENT it emits and the source of the scent), incense (same thing, they use oils to produce the scents emitted by incense, whether it is all-natural or not), any type of sprays, things you "plug-in" that emit scents/odors, etc. Birds have extremely complex and unique Respiratory Systems, as they all have Air-Sacs that are responsible for their breathing, as well as their ability to fly. Birds do not have diaphragms, nor do their lungs inflate when they breathe. It's all done by their Air-Sacs. So if you introduce any type of poison, toxin, or even IRRITANT into their Air-Sacs, they can't breathe.
And that's forgetting that many all-natural or Therapeutic Grade "Essential Oils" are toxic/poisonous to birds once they reach their blood-streams after they breathe them in. One that comes to mind is Tea Tree Oil, which is almost instantly fatal to birds if they breathe enough of it in...And there are many, many, many other Essential Oils that are just as poisonous/toxic to birds...So again, it has nothing to do with whether an Essential Oil is "all-natural" or "Therapeutic Grade", as being all-natural means it's coming straight from it's natural source (such as a plant, tree, etc.), and these natural sources are also toxic/poisonous to birds...
****The best thing you can do is not burn ANYTHING around your birds, including any Essential-Oils...However, knowing that not everyone will abide by that rule, then the second-best thing you can do if you absolutely must burn/diffuse Essential-Oils around your birds is to please do thorough research on EACH, INDIVIDUAL ESSENTIAL-OIL VARIETY before you burn/diffuse it around your birds, and make 100% certain that it is not a variety of Essential-Oil that is going to hurt your bird, make your bird sick, or kill your bird. Do a very thorough Google search for each, individual variety of Essential Oil (not the "brand" or "grade", but each, individual variety, for example Peppermint, Orange Oil, etc.)...And look-up each individual variety of Essential Oil with several different sources to verify. And if you can't find any information on an Essential-Oil variety and whether it's safe for your bird, then just don't use it.
There are a lot of websites that have massive lists of Essential-Oil varieties that are NOT SAFE for use around birds, as well as types of wood (trees) plants, etc.