The SPF of a sunscreen cannot be accurately predicted by only considering the amount of UV filters/protective agents added to the mixture because factors such as application mode, UV exposure and skin type affect the results. More accurate results can be determined by In-Vivo or in-vitro testing methods
There are certain international standards that are complied to when needing to test the SPF of a product. UVB is typically tested by In-vivo or in-vitro methods. In-vivo testing involves testing the product on human subjects where in-vitro involves testing the product on artificial substrates such as fused silica substrates. UVA is typically tested by using a critical wavelength spectrophotometer
UV radiation can cause severe skin damage from pigmentation, erytherma, premature wrinkles and even dangerous skin cancer. UV exposure has a cumulative effect over time on the skin. The sun give ore exposure of UVa versus UVB rays. UVA tends to penetrate the deeper layers of the skin causing aging and wrinkles where UVB causes immediate damage.
Sunscreen products contain inactive ingredients that can assist chemically and/or physically by absorbing or reflecting UV light.
Sunscreen Simulator Usage
NB: Please note that this simulator is only to be used as a guideline. In order to be sure of the actual SPF, clinical testing will have to be performed on the final product.
How to use the simulator:
- Fill in the % of concentration you wish to add to your formula by taking into account the maximum allowable concentration:
- As you fill in the concentration values, the SPF will be calculated.