Lowerst Amount of BB to Use

Hi, To make my gear, I have always followed a rule of BA of 0.02 and BB at 0.018. To make my it. I was thinking of lowering my BA to 0.010. I know that BA kills germs etc. So that leaves BB to bind the powder to the oil. What do you guys think would be the least amount of BB i could safely use. I’m open to any food ideas.

Thanks Gaza246