fashion

Cold Protection: A need for cold region body wearers

Introduction:

Will you be working outside this winter? You probably already know that the best protection is dressing with perfect wear. But do you know what materials work best to keep you warm? System design of cold weather protective clothing is a critical process, as it involves consideration of the effects of a number of external and internal parameters like environmental factors and physical, physico-mechanical and psychological parameters. The bulk and weight of the textile materials used in cold protective clothing plays very important role in deciding the performance of the garments, it should be as low as possible, so that the clothing does not create physical stress and discomfort to humans and does not affect their daily duties adversely. The primary function of cold weather protective clothing is to protect the individual from the natural environment. For civilians, the designing of protective clothing is simple, as the only requirement is protection against cold, whereas for military personnel, hill climbers, and other paramilitary forces, besides thermal insulation, a number of other requirements are also important.

Requirements of cold protection:

Ease of handling combat and operational hazards, accomplishing their mission with the clothing on their body, protection against rain, snow ingress, and extreme conditions of cold and wind. All the above requirements have to be met by the protective clothing, and at the same time the wearer should not feel any discomfort.

1. To repel water and snow.

2. To prevent heat from dissipating to the environment.

3. To give comfort to the wearer by preventing the body heat from escaping out more rapidly than it is produced or to enter the cold to the body because the lower the rates of heat flow, the greater is the heat resistance of the material.

4. Moisture repellent because the moisture increases the rate of conduction, because water fills the fabric voids and conducts heat more rapidly than air.

5. Clothing must permit the moisture vapour to flow out of the clothing to avoid condensation of sweat inside the clothing at low temperature.

This review discusses the essential factors involved in designing and developing of cold weather protective clothing and different insulating materials available for the weather protection.

Wool is a truly unique natural fibre with excellent warm properties. Wool is generally obtained from animals such as sheep, cashmere from goats, mohair from goats, etc. To protect oneself from extreme cold weather, wool is the perfect material to keep warm compared to acrylic and cotton.

Wool has several different qualities that distinguish it from other fibres. Some of the characteristics are crimps, scales, elasticity and it grows in staples (clusters). Wool’s scaling and crimp make it easier to spin the fleece by helping the individual fibres to attach to each other, so they stay together. Because of crimp, wool fabrics have greater bulk than other textiles and they hold air which causes the fabric to retain heat. Also when oiled and tightly woven, it is waterproof to some extent. Wool makes a great choice for clothing that can insulate you from both cold and heat. And an added bonus is that, it is fire-resistant. One of the great properties of wool is that it readily absorbs water due to its structure and chemical composition. Water binds within wool’s structure through the action of hydrogen bonds. The water enters the amorphous region of the intercellular cement and the matrix of the fibre within the fibre cortex, where the pore diameter is as small as 4nm. The moisture absorption and desorption characteristics of wool provide important functional characteristics to wool garments. As a result, wool acts as a buffer, absorbing the extra moisture quickly and dissipating it gradually. All fibres do this, but wool’s performance is superior and faster. So in typical winter conditions, it can provide real benefits to the wearer. Because of their crimped nature, when wool fibres are packed together, they form millions of tiny air pockets which trap air, and in turn serve to keep warmth during winter. When moisture is absorbed, tiny amounts of heat is generated. This warmth acts to prevent condensation in construction cavities by maintaining the temperature above the dew-point in damp conditions. While absorbing moisture wool releases energy in the form of heat, thus raising the temperature of its surrounding areas. Even when wet, wool has great wicking abilities and lasts forever. Actually wool absorbs water from both your skin and the atmosphere around you to create dry and warm environment around your body. So to protect yourself from extreme cold weather, as compared to the other fibres wool is the perfect material to keep you warm. Hence woollen wear is a necessity for winter, especially in temperatures of 0 degrees and below. Merino wool is one of the most fine and versatile amongst the natural fibres for its ability to keep the wearer warm in cold temperatures and cool and fresh in the hottest climates. For winter apparel major uses of wool are sweaters, hats, gloves, coats, scarves, blankets, drapes, etc.

Thinsulate:

Thinsulate is one of the synthetic fibres for thermal insulation used in clothing. Generally it is thinner than the polyester fibres. Thinsulate is more effective due to increased density of fibres and decreased size of fibres. Like most insulating materials, the gaps between fibres not only reduce heat flow, but also allow moisture to escape. These insulating fibres are beneficial for retaining some of the heat produced by body like sweat and other energy. Another great property of thinsulate is its thin-ness. It is considered as ‘the warmest thin apparel insulation available’. The major drawbacks of this fibre are its durability and it resists becoming wet. Unfortunately, it lasts less than five years. Hence its production is carried out on small scale.

Down Feather: