Keela’s System Dual Protection (SDP) offers unrivalled protection when it comes to waterproofing and breathability in any conditions.

WHY? – SDP is a unique double layer fabric system with an “Air Gap”. The tough/durable outer layer ensures it can handle wear and tear while a lightweight inner layer offers comfort and creates the 'Air-Gap' to build up warmth. SDP is 100% waterproof, breathable, warm and reduces inner condensation to keep the wearer protected.

SDP is used in tough and extreme conditions by Mountain Rescue Teams, Police Forces and Military users all around the World and is trusted by its users.

Scientific research shows that ALL single layer waterproof and breathable fabrics stop working after one hour of use in wet and cold conditions. The real weather when waterproofs are required to work.

The current industry testing standards for breathable waterproof fabrics is unrealistic. The standard emulates a typical day in the Sahara Desert rather than the wet conditions that outdoor enthusiasts can be caught up in.

SDP is the ONLY waterproof and breathable performance system in the world.

THE SDP FACTS

• An outer fabric, which is coated or laminated with a breathable membrane.
  
• An inner mesh lining, which has a high wicking hydrophilic membrane laminated to it.
  
• The two layers of fabric increase durability and create an “Air Gap”.
  
• The “Air-Gap” provides a natural thermal barrier, protecting against heat loss.
  
• The “Air-Gap” reduces the need for further layers underneath.
  
• The hydrophilic (water loving) membranes rapidly transport moisture (sweat and condensation) away from the body, keeping you dry and comfortable, even in the rain.
  
• These moisture removing hydrophilic membranes reduce condensation next to the body.
  
• SDP helps to regulate the body’s temperature, minimizing shivering when inactive.

THE SCIENCE
Weather conditions affect the breathability of ALL fabrics and garments. During heavy rain and low temperatures (around 0C to 10C) breathable, waterproof garments stop breathing and experience the ‘occurrence of dew point’ or ‘cold-bridging’. This results in a build up of condensation. A warm body at 37C will struggle to cope with these conditions and the wearer becomes uncomfortable if the moisture and condensation is not moved away from the body.

SDP uses two layers of fabrics with hydrophilic membranes and an “Air Gap” in between, to reduce the build up of condensation. The operating principle can be compared to double-glazing systems used for windows, which stops warm air coming into direct contact with cold air. The “Air-Gap” also acts as an insulator to keep in body warmth. The best insulator is air!

The two layers of SDP then ensure the garment remains breathable in cold, wet conditions by a “mechanical” means. The outer layer is a waterproof, breathable fabric with a hydrophilic laminated membrane, so does the work to protect from outside conditions. The inner layer is a revolutionary high wicking liner, laminated onto a hydrophilic film. This inner layer acts like a sponge, absorbing any moisture or water vapour inside the jacket and transporting it away from the body. This acts like a one-way valve taking moisture and condensation away from the body through the lining and into the “Air Gap”; the waterproof laminate ensures the moisture cannot wick back through to the body. It therefore passes through into the “Air Gap” and escapes either through the breathable outer layer at its own rate or by force mechanical ventilation of the “Air Gap” by movement of the wearer.

CONCLUSION
Single layer breathable fabric garments do not work in cold and wet conditions. Only the use of a dual layer system of garment construction with an “Air Gap” and mechanical ventilation works in these conditions!

Research by the University of Leeds shows that microporous and bicomponent fabrics decrease in breathability as the ambient temperature decreases. However, hydrophilic fabrics, as used in System Dual Protection, still continue to breathe consistently as the temperature drops