Exposing Exposure Schedules

A: The exposure schedule printed on a piece of tanning equipment or found in the unit’s user information booklet indicates the appropriate length of a tanning session for each skin type. It is derived as a result of testing performed on a unit equipped with a specific UV lamp product.

Testing generally is performed by the equipment manufacturer or at an independent laboratory at the manufacturer’s request. Total irradiance is measured and weighted with the effectiveness of erythemal and melanogenic action spectra at each UV wavelength from 260 nanometers through 400 nm. The Food and Drug Administration requires this testing, certification and labeling before a tanning unit can be marketed in the United States.

An exposure schedule is based on the minimal erythemal dose (MED) for each skin type. An MED is the least amount of UV exposure a person can receive and generate pigmentation while avoiding sunburn. Taking into account the spectral output of the equipment and the tanning capabilities of a particular user, the dosage (in terms of length of session) is calculated and translated into the exposure schedule that is on the label of all indoor tanning equipment.

In the United States, the exposure schedules reflect graduated exposure times— exposure starts slowly (0.75 MED) and increases carefully to the maximum exposure time resulting in a dose of 4 MEDs, which is the maximum session time for tanning equipment marketed in the United States. The maximum session time is the same regardless of equipment size and number of lamps, whether it is a bed or booth.

Professional tanning salons will follow these graduated exposure times and will take the time to properly skin-type and educate their customers about responsible tanning.

Q: How often is a person allowed to tan?

A: Since 1986, the Food and Drug Administration guidelines suggest that a 48-hour time interval should pass between tanning sessions. Pigmentation and/or erythema (sunburn) may not be fully visible for 12 to 24 hours. Therefore, two tanning sessions within a 24-hour period could cause an unintentional burn. In general, maximum pigmentation should be built up gradually—without a erythema-contaminated tan—by following the exposure schedule during eight to 10 tanning sessions. Once the desired result is obtained, maintenance tanning sessions of once or twice weekly usually will maintain the depth of a tan.