No idea, it probably is, but I've found it simpler to cut piece out of the wall and replacing it with metal or plastic mesh.
My 50 litre smart store has a ventilation area of 300 square centimeters (15*20cm), my 30 litre box has two 100mm holes and my 15 litre box has one 100mm hole, and I think they work well. 93 3mm holes equals to about 26 square centimeters.