HOBO/Onset CO monitor

["Kirk R. Smith" <krksmith@uclink4.berkeley.edu>]

A quick note to say that we have been using these devices with reasonable
success in China for about 6 months to do indoor air monitoring and have
done so in pilot work in Guatemala as well where we hope to use them over
a 2-year period for both area and personal monitoring.  They are not
as robust as Drager or similar small commercial datalogging devices and
there seem to be a significant fraction of lemons (which the company has
to date not been willing to exchange), but, for our purposes, their low
cost makes up for these faults.  We have not tried them for
emissions testing, however.

Here, for example, is a typical calibration curve showing excellent
agreement with, in this case, certified CO span gases of 4 different
concentrations: