Sunbathers' application of sunscreen is probably inadequate to obtain the sun protection factor assigned to the preparation

Photodermatol Photoimmunol Photomed. 1992;9(6):242-4.


The sun protection factor (SPF) is a ratio that estimates the protective efficacy of a sunscreen against sunburn. The generally accepted methods used to determine the SPF of a sunscreen require that the formulation be applied in a thickness of 1.5 mg/cm2 (Deutsches Institut für Normung) or 2 mg/cm2 (US Food and Drug Administration). The applied thickness of a sunscreen is important for the degree of photoprotection. Forty-two volunteers on a beach applied their own sunscreen all over the body. The amount of the applied sunscreen was on average 0.5 mg/cm2. This indicates that the labelled SPF is probably considerably higher than the obtained degree of protection against sunburn.

MeSH terms

  • Adolescent
  • Adult
  • Child
  • Female
  • Heliotherapy
  • Humans
  • Male
  • Sunburn / prevention & control*
  • Sunscreening Agents / administration & dosage*


  • Sunscreening Agents