wrote:
Interesting.... I wonder if the oposite has also happened. I tend to
use a lot more O2 than others using the EDS at similar altitudes; more
than different breathing patterns and/or metabolism would easily
explain.

The EDS depends on the regulator supplying the correct pressure (15
psi). If the pressure is higher, you will consume more oxygen, and vice
versa. This was the case for a friend of mind (20 psi, I think), and MH
replaced the regulator free. The outlet pressure is easy to measure with
any gauge that can measure 15 psi accurately. I've used a good car tire
gauge.

Given that these devices are calibrated by the factory prior
to shipment , and, presumably, could shift, do they ever require
checking and recalibration?

I had this done by MH when I visited their facility. It took only a few
minutes to check the electronic functions and oxygen delivery. I believe
MH will do this for free, if you send your unit to them, but you might
have to pay for the shipping both ways. Contact them - it's been a few
years since I asked.

For those using this device w/out
reference to an oximeter, such checking and recalibration might well be
important.

I agree, but with suitable oximeters costing only $200, there is little
reason to do without one. At least, talk your buddy into buying one so
you can borrow it, or casually mention to his wife that it makes a great
Christmas present! "Deviousness in the pursuit of safety is readily
excused" - author unknown.

--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA