If there is no pain and no decrease of vision and your husband does not "free bleed" and is not on coumadin/warfarin then as jms1182 suggests the most likely diagnosis is subconjunctival hemorrhage which is very common, very scary looking but a benign problem (it's like a bruise on the eye and could happen even from a cough or heaving lifting).
JCH III MD Ophthalmologist
Just a thought - take a read up on subconjunctival hemorrhage.