EN13537 Standard for Sleeping Bags
If two manufacturers says their sleeping bags will keep you warm even on colder nights how do you know who is telling the truth? The EN13537 Standard was introduced to give a standard scale of reference so that the consumer can compare sleeping bags from different manufacturers using the same 'yardstick'. All reputable sleeping bag manufacturers have sent samples of each of their bags to the world renowned Hohenstein Institute in Germany for testing to obtain temperature performance ratings under the EN 13537 Standard.
The temperature ratings are as accurate as scientific measurements can be and can assist consumers in choosing the appropriate sleeping bag for their intended activity.
The EN 13537 test is conducted under controlled conditions using a manikin that has separate heating zones & temperature sensors to simulate an actual human being asleep in a sleeping bag.
This detailed test provides accurate information on the range of utility of a sleeping bag - the determination of a comfort, limit and extreme temperature rating.
Comfort Zone: The comfort zone indicates a temperature range making sure that campers feel comfortable throughout the night.
Extreme: The extreme temperature rating is the lowest temperature at which the sleeping bag will perform.
Note: Despite this extensive testing, temperature ratings remain subjective and should only be used as a guide. Quality of clothing, differing ages, ground temperature, whether or not a sleeping mat is used are all external factors which may affect the effectiveness of a sleeping bag.