Tint rating for swimming goggles
What does SW0, 1, 2, 3 & 4 mean for a swimming goggle?
If you look at the additional information for all our swimming goggles, you will see a section called ‘Lens tint colour’. Under this there is an SW rating, which indicates the tint as assessed under ISO 18527-3:2020, the standard applicable to swimming goggles.
For prescription swimming goggles, the tint category should be considered separately from the refractive prescription. The prescription corrects the wearer’s vision, while the tint category relates to light transmission and visual comfort.
Light protection and glare?
The tint rating describes luminous transmittance: the percentage of visible daylight that reaches your eyes through the lens. A lower tint category lets more light through and is usually better for indoor pools, cloudy conditions or low-light swimming. A higher tint category lets less light through and can make bright outdoor conditions more comfortable by reducing brightness and glare.
Choosing the right tint is often a matter of preference, but as a guide:
- Clear or very light lenses: best for indoor pools, evening swims and darker conditions.
- Medium tinted lenses: suitable for mixed indoor/outdoor use and moderate daylight.
- Dark or mirrored lenses: best for bright outdoor swimming, open water and strong sunlight, where glare reduction is helpful.
What about UV protection?
UVA and UVB are invisible forms of ultraviolet light from the sun. A lens can have a light or clear appearance and still provide UV protection if the lens material and/or coating are designed for this.
Swimming goggles are made with polycarbonate lenses, which naturally offer excellent UV protection, inherently cutting out almost 100% of both UVA and UVB.
This being said, they are not classed as sunglasses and should not be used as such. They are not for direct observation of the sun, nor protection against artificial light sources e.g. solaria.
