[DownTownTonyBrown]

The purpose of the rule is not to just have another rule to enforce. The purpose is to protect the players from blood born pathogens (hepatitus, HIV)- those pathogens are only a danger to others when they can be transferred.

Transferability should be your guide as you judge whether a uniform needs to be exchanged/removed.

Even transferability is conservative because not only does there need to be enough blood to transfer but there must also be an opening on the receiver (open wound, eye, mouth) for the blood, and it's pathogens, to be transfered into. And obviously (rather unrealistically) we assume all blood is contaminated with these pathogens.

This conservativism is because the consequences can be dire.

Transferability. Balance your desire to get that blood off of the court with the inherent conservatism, the potential consequence, and the ability of the team to comply with the rule (if clean jerseys are readily available, maybe you want to get rid of a spatter).