Version Management, MRP and Safety Stock

Hi

can anybody clarify for me how MRP handles the safety stock level on the product-site record where the product is version managed?

if we have multiple active versions of the product - lets say 3 and we have a safety stock level set at 10. does this mean that MRP will consider that we require 10 as a total across all 3 active versions, or will it consider that we require 10 at each version level so a total stock holding of 30 will be carried.

thanks for any advice

John