Camping Sleeping Bag Temperature Ratings EN13537
Recently I was looking around for a replacement Sleeping bag and had to spend a lot of time working out the rating standards which are now applied. I though I’d add this article which came from a manufacturer to our site as reference for others. As this is for my boy and he’s just under the 60kg rate, I’m using the comfort rate to select his bag
(Article as received)
EN13537 is a non-mandatory standard for sleeping bag temperature ratings that was introduced into Europe in January 1st 2005, it consists of the following standardized test and measurements for determining sleeping bag temperature ratings:
The EN13357 temperature tests use a thermal manikin which is a full size humanoid dummy with heaters and temperature sensors. The manikin is placed inside the 
sleeping bag and both are placed in a climate chamber. The manikin is heated to simulated body warmth. The air temperature is measured in the climate chamber and on the skin surface of the manikin. From these measurements, the insulation value of the complete sleeping bag is calculated.
The temperature recommendations are defined by EN13537 based on the measured insulation.
EN13537 produces four temperature results – upper limit, comfort, lower limit and extreme.
These give ratings for a standard man weighing 80kg and for a standard woman weighing 60kg.
• The EN13537 Upper Limit or Maximum Temperature is the highest temperature at which a ‘standard’ adult male is able to have a comfortable night’s sleep without excess sweating.
• The EN13537 Comfort rating is based on a ‘standard’ woman having a comfortable night’s sleep.
• The EN13537 Lower Limit is based on the lowest temperature at which as ‘standard’ adult male is deemed to be able to have a comfortable night’s sleep.
• The EN13537 Extreme rating is a survival only rating for a ‘standard’ adult woman. “In the risk range a strong sensation of cold has to be expected and there is a risk of health damage due to hypothermia.”
This is an extreme survival rating only and it is not advisable for consumers to rely on this rating for general use. The best guideline temperatures for purchase decisions are the TComfort and TLimit ratings.
(above is an extract from EN13537 – Sleeping Bag Standard Information)
Generally speaking when selecting an appropriate sleeping bag for a woman the comfort rating should be used, whereas when selecting a sleeping bag for a man the Lower Limit can be used. The extreme rating should not be considered as it is a survival rating.