All About Sleeping Bags

All Sleeping bags conform to Euro Standard EN13537 to determine the temperatures that they are best suited. These tests determine:

Maximum Temperature:

The Maximum temperature represents the upper limit at which the average man can sleep without generating perspiration.

Comfort Temperature

The Comfort temperature represents the lower limit at which the average woman can sleep comfortably

Limit Temperature

The Limit temperature represents the lower limit at which the average man can sleep comfortably

Extreme Temperature

The Extreme temperature represents the temperature at which the average woman may suffer from hypothermia after approximately 6 hrs.

Sleeping Bag Design and Function

Down or Synthetic

Down

Down is a superior insulator per weight and is used for lightweight bags or cold conditions. Down is soft and comfortable, fills the volume in the bag and transports moisture from the body more effectively than synthetic fibres.

Down compresses more easily for packing, takes up less space and when treated correctly is more durable than synthetic. The insulating property of down is directly related to its ability to loft, which depends on its ability to expand after being compressed for carrying. One disadvantage with down is that if it gets wet it loses its loft and therefore its ability to insulate.

Down fill is measured in cubic inches. The higher the figure the greater the insulation and values above 500 are generally accepted as better than any synthetic fibres.

Most down bags are constructed with a box, or channel, construction which are overfilled to ensure good insulating properties.

Synthetic

Synthetic fibres are usually heavier, but cheaper, than down. How much cheaper depends on the weight, softness and compressibility of the fibres. A heavy fibre will be stiffer and heavier producing lots of air pockets which will cause greater heat loss but better durability.

The lighter synthetic fibres are similar to down but its insulating performance may not be as good. The advantage over down, however, is its ability to tolerate moisture with greater efficiency and will keep its insulation properties even when damp.

Synthetic bags varied insulation properties is provided by different shape and type of fibres used in combination to provide the desired temperature rating.

In other words, a synthetic bag is more practical than down for regular use and is more durable when used in harsher environments.