[QUOTE=Poweranger;20643186]. I do not plan on ever pouring gas down my floor drain so I didn't vent it.
Nobody "Plans" to pour it down the drain but you can imagine the 1001 ways it happens. Also, heavier than air gasses such as propane can leak in your garage and pour themselves down the drain (invisible to you). I recommend a vent. Trapped fumes can linger for a long time and bite you in the ass when you least expect it. I learned this from rebuilding boats.