so I did a comparison of 5 non inflatable sleeping mats last week. Some of the criteria were naturally subjective as its a personal thing whether you are comfy or cold etc. If you recall a combination of the scores for the 5 criteria put the Gossamer Gear Thinlight at the top and the OMM duopad at the bottom. I then got to thinking about the warmth of the pads and trying to apply some science and hard data to it.
In line with this thinking and borrowing ideas from BPL, I decided to test how insulative the 5 mats were using a digital thermometer. The idea was to place a mat over the thermometer measuring point, place a foil tin on top of that and then add 250ml of boiling water. Then using a stop watch, record the temperature over 15 second intervals until 90 seconds had elapsed.
I did this for the 5 mats and also for a foil tin without any mat as a control. The results are as follows :
|MAT / TIME (sec)||0||15||30||45||60||75||90||ave rise per sec|
|OMM duo mat||23.4||25.7||27.4||28.7||30.6||32||33.1||0.11|
|3mm laminate underlay||23.6||26.4||30.2||33.5||35.7||37.4||38.5||0.17|
From the above its clear that the radiator material is the worst followed by the laminate flooring material and then the duomat. This is at odds with my perception of warmth. Obviously the measurements I made are based on conductive heat transmission and in this case on high temperatures rather than low but the principle is the same. I was quite surprised at the radiator material being so poor but then it has a reflective surface rather than a insulative material per se. I was even more surprised that the duomat was more insulative than the laminate insulation (which felt very warm).
Anyway, if I substitute the actual results from above into my original scoring matrix, it puts the reflective radiator material as the worst performer. The laminate comes in 4th and the duomat takes third place. The torso pad and thinlight pad remain at 2nd and 1st respectively. This puts the duomat in a new light and although not fabulously comfy it does appear to be a reasonable proposition for use as a sleep mat outside of winter. And of course it does already form part of my OMM rucksack back support.
Science over perception