Hohenstein measures sleep comfort
The Clothing Physiology Department at the Hohenstein Institute in
As a result, its scientists are now able to compare the properties of different materials and provide references for optimising the structure and materials used. When it comes to measuring the moisture permeability (breathability) of materials, the technologies developed at Hohenstein using a skin model in accordance with the EN 31092 and ISO 11092 standards have been proven to produce demonstrably more significant results than other methods. In addition, they can be reproduced at any time and as a result offer and opportunity to compare different products objectively.
Scientists at the Institute have shown that the thermal insulating effects of a bedcover play a particularly decisive role in managing warmth. The principle has always been that the thicker and heavier the cover, the better the thermal insulation. However, research has shown that in developing modern bedcovers, the aim is to produce a product that provides thermal insulation that is tailor-made to the individual, while keeping the weight of the blanket as low as possible.
On the basis of their investigations of bedcovers, scientists at Hohenstein have defined three thermal classes to ease orientation for retailers and consumers. By using a simple graph, the suitable thermal insulation class can be determined individually from the ambient nightly temperature in the bedroom and the body weight of the person sleeping. The lower the ambient temperature and the weight of the person sleeping, the greater the thermal insulation class required. For example, a person with a body weight of 50 kg produces just 62 watts in thermal energy, while a person weighing 110 kg produces 101 watts. Yet the same skin temperature is necessary for each to feel comfortable and maintain body functions when sleeping. Therefore, the thermal insulation of a blanket for relatively lightweight individuals should be greater.
In addition to featuring optimal thermal insulation, bedcovers should also have the capacity to conduct excess heat and perspiration away from the body of the person sleeping. Hohenstein researchers have evaluated textile materials using several methods, including a skin model. They worked with different textile parameters that each represented a specific material property, including the management of moisture. Over several years, the specialists have developed a complex predictive model that can be used to evaluate thermophysiological comfort of a finished product. This is presented in the form of what is known as a "sleep comfort mark", which ranges from one for "very good" to four, for "inadequate". Once the optimal individual thermal insulation class has been determined, the sleep comfort mark is a decisive factor in selecting a suitable bedcover.
