RECTANGULAR SLEEPING BAGS
Rectangular sleeping bags have 2 advantages: They offer increased freedom of movement and when zipped open they can be used as quilts.
MUMMY-SHAPED SLEEPING BAGS
In comparison, mummy-shaped sleeping bags have a narrower cut to reduce “dead-air space” and therefore more thermally efficient at retaining body heat.
- offers enhanced insulation compared to the same weight of synthetic fibre
- packing size is reduced
- offers an unrivalled sleeping comfort
- it can absorb moisture and humidity to many times its own weight, leading to an almost complete loss of its insulating power
- as a natural product it is significantly more expensive than synthetic fibre
- is considerably more resistant to moisture
- does not absorb as much moisture when used on consecutive nights
- retains most of it’s insulation power even when damp
- has a somewhat larger pack size
- weighs slightly more for the same thermal efficiency
All sleeping bags are tested for their thermal efficiency according to international standards (EN 13537). In this way the customer has a temperature value with which the performance of the product can be estimated. Despite this, it is important to remember that these are laboratory bench-mark values only, as individual sensitivity to cold depends on many physical attributes.
- Level of fitness
- Level of exhaustion
- State of health
- Momentary physical condition
- Nutritional state
- Duration of the stay outdoors
- Efficiency of the insulating pad
Naturally other factors such as air humidity, wind, as well as night-time and daytime temperature variations also play a decisive role. So when in doubt – better too warm than too cold.
The sleeping bag norm EN 13537 came into effect in 2005. It was introduced to make the temperature data transparent for the end user. The norm includes 3 values:
1. Comfort temperature range (Tcomf):
The value for an average woman (25 years old, 60 kg, 1.60 m), who is just not feeling cold yet.
2. Comfort-limit temperature range (Tlim):
The value for an average man (25 years old, 70 kg, 1.73 m) who is just not feeling cold yet.
3. Extreme temperature range (Text):
The value for an average woman (25 years old, 60 kg, 1.60 m) under extreme cold conditions—running the risk of hypothermia.