Abstract: Low-pressure mercury vapor discharge lamp for suntanning purposes comprising a tubular discharge vessel which is provided on the inside with a first luminescent layer comprising a first luminescent material which emits mainly UVA and with a second luminescent layer which comprises a second luminescent material which emits mainly UVA, the two luminescent materials also showing mutually different UVB emission contents. At least one of the two luminescent layers extends over only part of the circular circumference of the discharge vessel with the object of obtaining different quantities of UVB radiation emission in different transverse directions of the lamp. The luminescent material having the lowest UVB emission is disposed on the wall of the discharge vessel and absorbs a portion of the UVB emission from the other luminescent material which is disposed closest to the discharge and has the higher UVB emission.