Estimating SPF for Your Sunscreen Formula

Determining the precise SPF value of a sunscreen formula requires laboratory testing. This is because the final SPF is influenced by how the different UV filters interact with each other and with the overall formulation, not just their individual percentages.

Your formula contains:

• OMC (Octinoxate) at 8%
• SPF Protect Ultra™ II at 3.5%
• Titanium Dioxide at 3%
• Silica Matte™ at 0.5%

OMC is an organic filter primarily providing UVB protection. SPF Protect Ultra™ II is a blend designed for both UVA and UVB protection. Titanium Dioxide is a physical filter offering broad-spectrum protection, and its effectiveness is highly dependent on the specific particle size and treatment used (as noted by the staff). Silica Matte™ is typically used for texture enhancement and oil absorption and does not significantly contribute to SPF.

Based on the combination and concentrations of these UV filters, particularly the organic filters and Titanium Dioxide, an estimated SPF could be around 30, as suggested by the staff. However, this is only an estimate.

To know the true SPF value of your specific formulation, you must send a sample to a certified laboratory for testing. As the staff mentioned, you can contact customer service for recommendations on testing facilities.