First time users are advised to spit out the first couple of mouthfuls (40 ml) as a small amount of harmless black carbon water will be expelled on initial use. (See user instructions)
First time users may find it difficult to start sucking. This is because a natural brake on the flow of water has been put into the LifeStraw®, as a controlled flow between 100 ml to 150 ml per minute is needed to get the maximum benefit of the bacteria killing effect.