THE NEW R-VALUE ASTM F3340-18 TESTING

How warm is this sleeping mat now?

Your sleeping mat is the foundation for a good night’s sleep and a critical component of your overall sleep system. Without an R-value that’s suitable for the conditions you’re sleeping in, even the best sleeping bag won’t keep you warm at night.

To ensure a warm night’s sleep, you need to know how well your sleeping mat resists heat loss into the ground. This resistance is known as an R-value (resistance value).

An R-value, tested in a laboratory to precisely-controlled standards, is the only way to know how well your mat will prevent your body warmth from being leeched away by your sleeping mat. Any ‘temperature rating’ associated with any sleeping mat is simply a manufacturer’s guess—it’s not tested and it’s probably not reliable.

Sea to Summit, and a handful of other design companies, have always provided independent lab-tested R-values for sleeping mats. And now more of the industry are getting on board, with the new industry standard ASTM F3340-18.

This is great news for consumers! It means they’ll now be able to rely on standardised, independent testing to make purchase decisions across different brands.

As of 1 January, 2020, we will be using the new industry standard ASTM F3340-18 test to provide R-values for our mats.

Sea to Summit, along with other industry leaders, have worked hard to define this new testing standard, which aims to achieve two things:

  1. Create a universal system that allows users to compare mats across brands
  2. Provide clear and transparent information to consumers

This new method of testing the insulative properties of sleeping mats will see some changes to our previously published R-values. It’s important to note that where these values change, it doesn’t signify a drop or increase in warmth—it simply means they have been tested using a slightly different scale.

As the new standard is integrated across the industry, we’ll be helping educate consumers on how the new testing works and how to use these readings to prepare for real world situations.

That’s the new ASTM F3340-18 R-value standard in a nutshell. For those who want to learn more, we’ll be releasing more information in the coming months.