There is a selection criterion for sun protection umbrella called UPF, short for the Ultraviolet Protection Factor (Ultraviolet Protection Factor), which is usually marked on the umbrella. The higher the UPF value, the better the sun protection ability of the parasol.
Sun umbrellas with UPF40 and above are considered qualified, and a good umbrella should reach 50+.
Generally speaking, a canopy with the thicker umbrella surface and tighter fabric has better UV resistance.Thick material and double-layer sun umbrellas have good heat insulation effect, and they are more worth buying. In addition, satin weave fabrics are the best for UV protection, followed by twill weave and plain weave. The darker the better. The color of the sun umbrella is closely related to its efficacy. If the inside of the umbrella is shiny, light-colored, it is easy to collect the ultraviolet light reflected from the ground, so that people will be tanned even if they wear the umbrella. Therefore, when people who are afraid of tanning choose sun umbrellas, they should pay attention to choosing dark products such as black or cyan.
Sun umbrellas on the market are divided into two types: ultra-light frame and alloy frame. It is generally recommended to choose the ultra-light frame, because the ultra-light frame uses aluminum alloy or acrylic material, which is light in weight and long in life. The general life span can reach about 6 years. But the disadvantage is that the skeleton is thick. The alloy frame is slender, which is usually used for pencil umbrellas. But they are heavier than thick umbrellas, and they cannot be used in rainy days because iron is easy to rust. The size and curvature of the umbrella surface are also important criteria for selection. The larger the umbrella surface, the lower the arc, the largest shading area and the best protection effect. It is like an upside-down bowl, hiding the body in a cool place. If you choose a sun protection umbrella in a physical store, you can test it in the sun yourself. Standing under the umbrella, the larger the shade, the cooler you feel, which means that the effect of the umbrella is better.