This method permits defined and standardised conditions for measurements, which are not influenced by biological factors such as pigmentation type, anti-inflammatory drugs, skin surface and individual technical variations (application, erythema, readings).In addition, the photo-stability of the sun protection substance can be determined.
In this context, the sunscreen is homogenously spread over a substrate and is then in accordance to the in vivo method irradiated using a solar simulator light source before the spectral transmittance is measured.
