Total organic fluorine.

TOF measures fluorine, not PFAS. A lab burns the sample and totals the organically bound fluorine, giving one number that stands in for thousands of possible compounds, so it answers whether fluorine chemistry is present rather than which substance and how much. Regulators lean on it because targeted analysis cannot keep pace: California's apparel and textile rule defines regulated PFAS as either intentionally added PFAS or presence at or above a threshold measured in total organic fluorine, 100 ppm from 1 January 2025 and 50 ppm from 1 January 2027. A screen result over the line is a trigger for questions, not a named chemical and not a count. For a decorator the consequence is upstream, since the fluorine sits in the blank's finish rather than in the ink, which is the point the PFAS entry makes. The answer to a TOF number is therefore a supplier conversation and the certificate of compliance the same law obliges the manufacturer to provide, not a test the shop runs itself.