Your clothes cover your skin, but ordinary fabrics may not offer as much sun protection as you might think. This blog post compares the protection offered by normal clothes and UPF clothes in order to understand the importance of sun protective clothing.
The Sun: Friend or Foe?
It can seem counterintuitive that one of the world’s greatest sources of life can be potentially damaging to our health. When it comes to sun exposure, too much of a good thing can be dangerous. It’s important to remember that being sun smart doesn’t mean avoiding the sun altogether. It’s about enjoying the sun whilst staying safe under it.
While most of us turn to SPF sunscreen as our first line of defense against sun exposure, the need to reapply and the recommended wait prior to exposure significantly contribute to sunscreen’s inconsistent coverage. Dermatologists recommend wearing sun protective clothing with a high UPF rating. Where SPF falls short, UPF material is unwavering in its ability to block up to 98% of UV rays, dismissing the need for the consistent reapplication of sunscreen.
What is UPF?
UPF stands for Ultraviolet Protection Factor and measures the extent to which fabric can block ultraviolet radiation from the sun. UPF refers to how much protection a particular piece of clothing will offer, and the highest achievable sun protective rating for fabrics is UPF50+.
The level of protection offered by different fabrics varies, and clothing with a UPF rating of 30+ or lower is not considered protective. A normal t-shirt typically has a UPF rating of 5, which means that 1/5th (roughly 20%) of UV radiation permeates its fabric and reaches your skin.
In contrast, sun protective clothing with a UPF rating of 50+ means that a maximum of 2% of all UV radiation reaches your skin. “That’s a significant improvement,” says Dr Deshan Sebaratnam, an Australian dermatologist specialising in skin health and disease.
How is UPF determined?
There are several factors that contribute to the efficacy of UPF clothing. In an article published by Bupa Health Insurance, Solbari’s Founder and CEO Johanna Young explains that the type of fabric, weave density, thickness and weight, colour, stretch, moisture content and fabric condition all determine the UPF rating of any one piece of clothing:
- Weave density: The tighter the knit or weave, the better. If the sun can penetrate your clothes easily, it’s not protective, no matter how much clothing you wear.
- The type of fabric: Some fabrics are more effective than others at blocking UV radiation. Some synthetic materials like acrylic, polyester, nylon and lycra or rayon tend to reflect more UV and are therefore more protective.
- Colour: The darker the better. You might be tempted to wear light colours in hot sunny weather, but the UPF rating is higher for darker colours because they absorb more UV rays, compared to the same fabric in a lighter colour.
- Thickness and weight: The thicker and heavier the better.
- Tension or stretch: The less stretchy the better.
- Moisture Content: When fabric gets wet, it tends to reduce the UPF of the fabric. For example, a thin white cotton t-shirt with a UPF of 5 may only have a UPF of 3 when wet.
- Fabric condition: As clothes age the fabrics are likely to deteriorate and this will also reduce the UPF rating.
“UPF clothing and SPF sunscreen are all elements of your armour that protect you from the sun,” says to Dr Sebaratnam. As great as UPF clothing is, we’re likely to not always be wearing it. Even if we were to do so, it is inevitable that parts of our body will be exposed to the sun at some point. It’s in these instances where SPF steps in to become our second line of defence against sun damage. It’s important to remember that not all sunscreens are as effective as others, so make sure that you opt for broad spectrum coverage which blocks both UVA and UVB radiation.