A Blra is part of the oncidium alliance. They require moderate light (dappled shade is good), high humidity, and more frequent watering (2-3x per week depending on the coarseness of the media)than something like a phal. They also need good air movement because they do require good humidity, this helps prevent rot. They have thin roots and can get accordion pleating in their leaves if the humidity/watering isn't sufficient. You can visit
AOS | Home and read the care sheet for oncidiums and this will give some more info about your blra
Hope that helps!