Fluoride Test

A semi-quantitative test strip for fluoride in water. Dip it, wait the stated time, and compare the pad against the colour scale on the tube.

Why it is measured

Fluoride has a narrow useful window: enough protects teeth, more than that mottles them permanently, and natural groundwater in some areas carries far more than any water authority would add. The number matters in both directions.

Where it is used

• drinking water supply
• well water screening
• fluoridation dose control
• dental health surveys

What a strip can and cannot do

A strip gives a range, not a figure. That is enough for the great majority of decisions — dose or do not dose, discharge or hold, keep running or stop — and it gives the answer where the sample is, in about a minute, with no instrument to calibrate and nothing to carry back to a laboratory.

When a number has to be defensible — a regulatory report, a dispute, a limit you are close to — a photometer or a laboratory method is the right tool. The strip's job is to tell you whether you need one.

Practical note

Aluminium and iron bind fluoride and hide it; a water high in either can read low and still be over the limit.

Supplied in one presentation.