Ultraviolet UVA and UVB rays, the two major wavelengths of sun enter in to skin through most of the lightweight apparel we wear and generate free radicals (corrosive molecules) that affect DNA cell function. UVA, called the "aging ray" generates 95 percent of UV light and UVB, the "burning ray" has a shorter wavelength but is stronger than UVA radiation, these radiation damages cellular proteins, lipids and carbohydrates, leads to brown spots on skins, skin cancer and various diseases.

In day to day life protecting the skin from these ultraviolet rays can not be ignored. Hence to protect the skin from these rays requires sun-protective clothes.

About sun protective clothing

The term "sun protective" explains fabrics or clothes exclusively made to safe guard the skin from UV radiation. In other words sun protective clothing is the attributed fabrics either treated with a proprietary UV inhibitor or woven to remove the penetration of dangerous UV rays to the skin.

Early studies disclose that various summer clothes which were used offered too little protection. In the past decades the majority efficient fabrics in the market were simply made of tightly woven, lightweight nylon or polyester. The most significant characteristics of sun-protective fabrics are: they must be tight in structure and dark colored. Closely woven or knit fabrics give the wide area of coverage, so little gap between the yarns permit less UV radiation to pass through the fabric and protect the skin from UV radiation. Deep and darker colors, such as navy blue, black, dark green and red prevent from harmful UV rays. Heat and visible light replicate light colored fabrics, but UV radiation permits through to the skin. Darker colored fabrics are more preferred than lighter colors and clothing made of tightly-woven fabric functions excellent at protecting skin from the sun. While woven fabrics that have holes in between threads permit UV rays to enter through to the skin and are not suggested for sun protection.

The concept of Breathability: Wicking" /"Breathable" fabrics: When clothing becomes wet from sweat it affixes with the skin and hold back the evaporation process. The evaporation process stays our body temperature at its proper level to maintain us cool in the summer and cozy in the winter. Cottons, nylons and polyesters have always been detestable for holding back our evaporation process. The new fabrics have one fundamental temperament, Breathability. They have extraordinary knitting that provides the facility to let our cooling process done, in which it wicks the sweat from our skin.

There are lots of various modes that the manufacturers have adopted this weave to the clothing industry. Many nylon fabric products also have a special weave that lets the steam out while keeping the wind and even the rain out. Synthetic fibers are non-absorbent, and also it is "breathable", so synthetics are known enduring and good fabrics for UV protection or sun resistance. But as compared to the latest UV protection fibers they are less efficient UV protector. Blending of cotton fiber with fibers such as polyester are also a good UV absorbers. Mesh is also an extremely breathable fabric that is utilized for making shirts, jackets and pants. Though it is not sun protective and should not be used alone for sun protection.

There was no availability of extraordinary chemical therapies for UV absorption or special sun protective fabrics in those days. But as the textile technology growth came out there are many protective fabrics and clothes are available in the market. Today, lightweight fabrics added with chemical sun blocks are also offered to for UV protection and these chemicals keep useful after many launderings.

Who requires sun protection?

. Skin cancer can set upon anyone, in spite of their tanning capability, age, sex or race,
. Travelers who most frequently travels,
. People those are allergic to the sun, making painful skin complaint and sore,
. Lupus flare-ups are generated by the sun and are specifically affecting to young women,
. Extended contact to the sun increases the chance of UV damage (i.e. outdoor workers),
. Sunburns from childhood amplify the risk of rising skin cancer,
. Immune inhibition treatment for removing recipients can reason of sun sensitivity,
. Particular medications source sun sensitivity-check and
. The immune structure of individuals getting chemotherapy and radiation are damaged and vulnerable to UV exposure.
Sun protective fabrics standard

In various countries governments regulated some standards for fabric or garment that creates particular profess of a medical nature. If the manufacturer declares the fabric stop skin cancer or protects against other health hazard, then they must follow standards and have to authenticate by precise testing. Generally United States' SPF measurement unit is used to calculate UV transmittance.

The sun protection factor, SPF, is a measurement of how much time a person can bare the sun before cause of burn. If you burned by sun in 15 minutes, treatment of SPF 30+ sun block would permit you 450 minutes in the sun before having burned. The new unit also existed for UV protection is named UPF (Ultraviolet Protection Factor) and is alike the sun protective factor SPF applied on sunscreen lotion bottles and fabrics, in that both UPF and SPF calculate sunburn protection. The only difference is that UPF measures both UVB and UVA radiation while SPF calculates UVB radiation only.
The new UPF fabric rating, also requests that fabrics maintaining sun protective measures must be equipped in the following ways before trying:
1. Undergo 40 repeat launderings,
2. Be bare to 100 evaporation units of simulated sunlight (equivalent to 2 years light exposure),
3. If anticipated for swim wear, acquaintance to chlorinated water.
The following is a comparison between the UPF and SPF ratings:



The American Society for Testing and Materials provided standards for labeling sun protection competency of fabrics by ultraviolet protective factor (UPF). It is parallel to the SPF applied to label sunscreens-the higher the number the better the protection.

According to ASTM,
UPF 15 - 24 = Good Protection, (blocks 93.3% - 95.8% of UV rays),
UPF 25 - 39 = Very Good Protection, (blocks 96.0% - 97.4% of UV rays) and
UPF 40+ = Excellent Protection, (blocks 97.5% - 98.0% of UV rays).

Factors that affects UV Protection Intensity to the fabrics

There are a many factors that influence the level of ultraviolet protection to a fabric and the UPF rating.
. Weaving (tighter is superior),
. Color (darker is superior),
. Weight (also called mass or cover factor - heavier is superior),
. Stretch (less is superior)
. Humidity (dry is superior) and
. Effects of affixing chemicals such as UV absorbers or UV diffusers.

For example a simple white cotton T-shirt gives only average protection from sunburn, with an average sun protection factor (SPF) of 7. While a long-sleeve dark denim shirt provides excellent sun protection - an estimated SPF of 1,700. Generally for good quality of cotton fabric the SPF of a green cotton T-shirt is 10 vs. 7 for white cotton, and a solid fabric such as velvet in blue, dark green or black, has an estimated SPF of 50.
Any fabric that stretchable in particular areas drops some level of UV protection, because the fabric becomes thinner and further transparent to light and wet clothing also creates a trouble with some fabrics such as cotton where it losing up to 50 percent of their SPF.

The sun-blocking properties of fabric are better when it dyed, pigmented or ultraviolet absorber finished which absorbs ultraviolet radiation and blocks its transmission through a fabric to the skin. So, dyed fabrics give superior sun protection than bleached fabrics. Since naturally-colored cottons include pigments that create shades extending from light green to tan and brown, practically it assumes that they would offer better sun protection than conventional bleached cotton. The tightly formed, darker garments give sufficient protection. For example, cotton denim blocks almost all UV rays.

The emerging technology in fabrics to protect the skin from sun

Of course, choosing closely assembled, dark fabrics for outdoor apparel importantly increases protection. Normal cotton and rayon fibers are not good UV protectors; they do not suck up adequate harmful UVB and UVA rays to be as protective as they should be. To protect the heat and sun burn there require a high efficient fabrics, though the textile technology developed gradually, there are many protective fabrics manufacturers are manufacturing high efficient protecting fabrics with UV protection chemicals in the market.

Manufacturing fabrics with high UV-absorbers such as resins is a further familiar approach for clothing manufacturers to raise the SPF of clothing. Of late, particular laundry detergents that including sun-protective additives are added to provide consumers a short-term benefits to the SPF of clothing.

Nearly all major manufacturers of fabrics have been introduced sun-protective products or fabrics. SolarKnit was chosen by a team of scientists at NASA's Johnson Space Center to provide as the fabric for space/sun suits for two British boys with a scarce complaint that needs absolute protection from sunlight. DuPont's Dupont Lycra fabric provides SPF/UPF 100+ protection.

Manufactured by Milliken Solarveil is a patented mesh-like fabric. The unusual open-knit permits for optimum breathability. Solarveil fibers are made with UV inhibitors to absorb the harmful UVA and UVB rays and made into a multifaceted mesh structure that replicates and refracts UV light. Solarveil oppose 70% to 80% of the UVA/UVB radiation with a single layer, and 90% to 95% with a double layer. Tests carried out by an independent laboratory proved that a single layer of Solarveil has an SPF rating of 20.To block larger than 97.5% of all UVA and UVB radiation Solarweave fabrics are manufactured.

Made by Burlington M.C.S. Blocker, keep up its 30+ SPF rating wet or dry even after, 40 home launderings, 100 hours of uninterrupted, intense revelation to light, high abrasion power. The newest superior performance technology in chlorine resistant material like Chloroblock TS, also gives UV protection to 50+ UPF. This sun protective fabric is particularly made to block greater than 97% of all UVA and UVB radiation.

Because of fabric construction and its twist sewing techniques also affects penetration of UV rays, for this nylon fabrics like SolarWeave is made to protect UV radiation.

Protective Steps

Skin not only gives as the outer covering of the body, but is a multifaceted system of dedicated tissues. Dermatologists suggest taking care of skin by sensible hazards of the sun. To protect from the sun stroke or sun burn keep in mid the following points, where ever you go.

. Wear long-sleeved pants, long-sleeved shirts,
. If possible keep away from outdoor activities between 10 a.m. and 4 p.m. when the sun's rays are the strongest,
. Wear loose, protective clothing, a hat, and sunscreen (SPF15 or greater),
. Make sure children are protected. Early childhood sunburns may create a great chance for improving melanoma,
. Self-examine your skin every month. Request your physician to check moles and skin areas that look doubtful,
. Dry fabric is usually more protective than wet fabric,
. A tightly woven fabric gives better protection than loosely woven clothing,
. Dark colors give more protection than light colors by preventing more UV rays
. Keep in mind to use sun protection swimwear, umbrellas at the beach and pool

Conclusion

The best way to avoid from UV radiation is to stay out of the sun as much as possible between 11am and 4pm. If you don't have that choice, and can't find clothing with a UPF rating, look for the following:

Weave - tightly woven fabrics are the best. Knit fabrics provide freedom of movement.
Fit - the protection will be lower when they're stretched, so go for a close knit and a loose fit, especially across the shoulders.
Colour - darker colours provide more protection than fabrics of the same material in light colours.

Protect the rest of your body with lashings of sunscreen (broad spectrum, SPF 30+) and a wide-brimmed hat.