Shelly Watson, lamp sales expert at JK-Light, has received several calls about UVB percentages and asked me to cover this topic again for those in the dark.
So, what are UVB percentages and what do they tell you about lamp performance?
There is no industry standard for determining UVB percentage, just as there isn’t an industry standard for determining Tingle Factor in a lotion. For example, a Tingle Factor 30 from Company A may perform completely differently than a Tingle Factor 30 from Company B. You may know that within the lotion lines from Company A that their 30 is stronger than their 20 and the same goes for Company B; however, you can’t compare Company A’s tingle to Company B’s tingle.
It’s the same with tanning lamps. The UVB percentage is just a number that companies use to market their lamps. UVB percentages are derived from dividing the measured UVB energy of a lamp by its UVA energy. This is a common method of “rating” sunlamps, but it is only a relative figure and tells us very little about a lamp’s tanning power, effectiveness or useful life. It is not an accurate measure of a lamp’s true performance.
UVB is a critical component for the production of melanin in human skin, which is then darkened by exposure to UVA. The total amount of UV energy, and whether the UVA and UVB are from the most effective spectral regions are the determining factors in a lamp’s performance.
Two sunlamps are shown in the simple graph below. Both deliver the same amount of UVB, but deliver greatly different amounts of UVA. Lamp 1 on the left has a five percent UVB ratio versus that of Lamp 2 on the right with only four percent. If one only looks to the UVB% values, Lamp 1 with its higher UVB/UVA ratio could mistakenly be construed as a stronger or more effective lamp. Not true: Lamp 2 has a lower UVB ratio because it delivers so much more UVA energy.
An effective sunlamp must produce a balance of both UVA and UVB. Adding more UVB typically creates a lamp that will produce more of a “reddening” effect, but does not make a better “tanning” lamp.
