So, to recap..
1) Blood only had to be poured out as a sacrificial offering after a life had been taken.
Blood from a live animal was never used in a sacrifice.
2) The law did not require that anyone eating any blood, in any circumstance, was to be declared permanently unclean and cut off from the people.
Examples of exceptions have been given.
3) Uncleanness under the Law was a temporary condition that could be changed once a person took the necessary steps. An act that made someone 'unclean' did not have to be sinful.
Uncleanness was unavoidable.
"From First Samuel 14:31-35 it may be deduced that “eating with the blood” means eating meat without first pouring out the blood before God, normally on an altar."
"What Was Done about Uncleanness
These regulations imply that one should avoid ceremonial impurity if possible, but the nature of the rules given above shows that often this was, even by natural biological processes, impossible. Everyone became unclean from time to time. Periodic states of uncleanness were unavoidable.
Where contraction of impurity occurred, it was obligatory that the unclean person avoid that which is holy and take steps, involving the rituals for disposal of impurity, to return to a state of cleanness."
"Uncleanness and the danger pertaining thereto lingered [only] upon those who did not take the necessary steps to be purified (Numbers 19:12-13; Leviticus 17:16)."