CO is only slightly lighter than air and diffuses pretty evenly. For home use detectors should ideally be at 5 feet, but homes are large and have warm air currents that tend to circulate it higher up.  For the compact van I'd put your multi detector low to detect the other gasses that do sink, and also always leave a window or the skylight  cracked open a bit.  

Stuart

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of Jared Planter
Sent: Sunday, March 19, 2017 4:20 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Multi gas detector location

Hey guys

I'm about to install this multi gas detector in our westy and I'm having second thoughts about installing it on the floor board of the rear bench.
Here's why. The device detects propane, methane and carbon monoxide. Carbon monoxide is lighter than air and will rise, propane will do the opposite.
Thus, this location would be good for propane detection but poor for carbon monoxide and the opposite for installing it higher up.

OR, am I over thinking this because the tiny space of a westy (80sqft) would fill up rather quickly anyways?

Thoughts?

Thanks,

Jared