Ultraviolet Protection Factor
The UPF rating indicates how effective a fabric is at blocking out solar ultraviolet radiation.
Testing is performed by ARPANSA (Australian Radiation Protection and Nuclear Safety Agency) according to Australian/New Zealand standard AS/NZS 4399.
UPF ratings range from 15 to 50, with higher ratings indicating more effective blocking, and therefore better protection for the wearer of a garment made from the fabric.
Fabrics that test higher than UPF 50 are rated UPF 50+.