| Skin type (appearance unexposed) | Critical dose mJ/cm2 | Self protection time (min) | Risk level |
| I. White | 15 - 30 | 5 - 10 | Burns easily, has the highest risk of premature skin ageing and greatest risk of developing skin cancer |
| II. White | 25 - 35 | 8 - 12 | Burn and only rarely tan |
| III. Brownish | 30 - 50 | 10 - 15 | Tan and occasionally burn |
| IV. Brown | 45 - 60 | 15 - 20 | Tan and occasionally burn |
| V. Brown | 60 - 100 | 20 - 35 | Sufficient levels of melanin and rarely burns, easily tan |
| VI. Dark brown-black | 100 - 200 | 35 - 70 | Sufficient levels of melanin pigment provide protection. Very rarely burns, easily tan. |