I might have endangered other divers' lives if I had spilled blood in the pool. (Para.3)
Meaning: I might have put other divers' lives in danger if my blood had poured in the pool.
spill: v. pour out; allow sth. to fall out of its place
He fell and the peanuts in his hand spilled all over the ground.他摔倒在地上，手里的花生撒了一地。
During a flood, the water from a river flows over its banks and spills onto the land around it. 发洪水的时候，河里的水溢过河岸，流到四周的地里。