Samples with ≤0.5 mL of pellet resuspended into 5 mL will require 1 Leighton tube. Samples with >0.5 mL and <1.0 mL of pellet resuspended into 10 mL will require 2 Leighton tubes, and so on.
For samples being analyzed for compliance with the Long Term 2 Rule, analyze all of the pellet resuspension, or up to 20 mL, transferred in 5 mL aliquots into 4 Leighton tubes.