To determine the proper lamp for a particular tanning unit, you are first required to follow the equipment manufacturer's recommended lamp replacement guide on the equipment label, and/or in the owner's manual. However, if a lamp other than the original equipment lamp is used, it must be compatible according to FDA guidelines.

In order for a lamp to be compatible to the original lamp furnished with the equipment, the output of the replacement lamp must, within +/- 10%, have the same erythemic and melanogenic effect on the tanner. The replacement lamp may not alter the exposure time of the equipment, which must be certified before the equipment can be marketed in the U.S. This certification verifies the minimal erythemal dose (MED), which is the least amount of UV exposure a person can receive without burning, while generating pigmentation.

It is important to note that compatibility is not defined as "same as or better than" the original lamp. Compatible lamps may have unequal life and different spectral characteristics. Different phosphor blends can and do produce completely different results. Thus, compatibility only addresses the issues of erythema and melanogenesis, and signifies nothing about the technical qualities of the lamp or the results you will see for your customers.