That depends on many factors:
As a rough guide, if you are wearing the type of clothes appropriate for the season and you make some effort to find a sheltered spot and put some insulation underneath you, then in spring, summer and autumn you should be warm and comfortable. In winter you may not be so comfortable, but you should be able to survive for several days in all but the most extreme conditions.
Surprisingly strong. Single layer reflective blankets are very fragile because they are easily punctured, and once a tear has started to develop, it rips right across the material. This doesn’t happen to Reflexcell™ material because:
Of course the material can be damaged (it should be kept away from sharp objects) but even if this happens, it will continue to keep you warm.
Technically the answer is no. Physicists tell us that whereas radiated heat can be reflected, cold cannot. It is true that if the surface of your body is cold, it will emit very little radiated heat, so that reflecting this back to you will only make a very small difference to getting you warmer. But it is scientifically impossible for a material to reflect cold back to you and make you colder.
Fortunately, unlike other reflective products, most of Reflexcell™’s warming ability comes from trapped air insulation, so even when there is very little effect from the reflectiveness of the material, this insulation will help you to get warm much faster than other reflective products.
If you compare Reflexcell™ products with single skin products, for example with polythene survival bags, or with space blankets, they might not look cheap. But they are actually a completely different type of product – equivalent to a traditional "bivvi bag” and a conventional insulating sleeping bag in one package. Polythene survival bags may protect you from the worst of the weather, but you will usually be cold, damp and uncomfortable. In cold conditions they will not stop you becoming hypothermic.
People who have used single layer reflective blankets in any but the most gentle conditions report disastrous results – blankets disintegrating when unpacked, ripping in the wind, and not even offering the illusion of warmth. Compare this with a product which will give you a comfortable night, even in cold conditions, which in a real emergency will keep you alive for a week, which will provide instant warmth and shelter and protect against hypothermia even if you are wet through.
Not normally. This is because the warmth of the material suppresses the formation of condensation, and the perforations in the inner and middle layers allow much of the moisture to move away from the body. However under certain conditions small amounts of moisture can form. No one who has used Reflexcell™ products has felt that these caused any problem, or affected the performance of the material.
Samples of Reflexcell™ material have been tested in the laboratory to measure their thermal resistance (insulating ability). Blizzard has conducted in-house tests, and independent tests have been conducted by Leeds University. Performance is measured in Togs, a unit of thermal resistance commonly used in the textile industry.
(1 Tog = 0.1 m2K/W i.e. one Tog is a tenth of a square metre degree Celsius per Watt).