What does it all mean?
In Europe, the EN 13537 standard normalizes the temperatures at which a sleeping bag can be used. Tests provide four temperatures:
Upper limit is the highest temperature at which a ‘standard’ adult man is able to have a comfortable night’s sleep without excess sweating. This rating is not normally used by sleeping bag manufacturers.
The three key rating to look at are:
Comfort rating is based on a ‘standard’ adult woman having a comfortable night’s sleep.
Lower limit is based on the lowest temperature at which a ‘standard’ adult man is deemed to be able to have a comfortable night’s sleep. 
Extreme rating is a survival only rating for a ‘standard’ adult man. This is an extreme survival rating only and it is not advisable to rely on this rating for general use.
So when you’re selecting a sleeping bag for your trip look at the temperatures you are likely to experience and pick a sleeping bag with a COMFORT RATING which matches the lower temperature you will find.
Getting a good night’s sleep!
When in your sleeping bag you lose more heat through the ground than the air, so it’s important to insulate yourself by using a good sleeping mat, we recommend an inflatable mat with built in insulation such as the Thermarest NeoAir or Exped Synmat (see: http://goo.gl/amdpp ), which both have built in insulation. While in your bag it’s also a good idea to tighten the shoulder collar and hood drawstrings in order to trap your body warmth inside the bag.
If you feel the cold, it may be a good idea to add a fleece liner to your kit list which will add extra warmth to your sleeping bag. Also getting up in the middle of the night for a pee is an easy way to get cold, so consider taking a pee bottle, to save getting up. For Outdoorhire’s selection of sleeping bags and liners which have been tested for their selected environment see: http://goo.gl/QOzi9
Special thanks to outdoorhire.co.uk for writing this blog for Charity Challenge.
2 Comments
this article is missing some key information namely body weights and what you should be wearing to bed I.e not just your pants.
“These ratings are taken assuming that the subject is using a sleeping pad, tent and is wearing one base layer of thermal underwear.
For the purpose of these measurements, a “standard man” is assumed to be 25 years old, with a height of 1.73 m and a weight of 73 kg; a “standard woman” is assumed to be 25 years old, with a height of 1.60 m and a weight of 60 kg”
why add a fleece liner? Shouldn’t you just use the correct rated sleeping bag which will weigh less than a fleece liner added to the incorrect rated sleeping bag?