Allergy alert test rules for hairdressers, and what insurers usually require

What the test is for

An allergy alert test is a small application of the mixed colour (or the product the manufacturer specifies) to skin, usually behind the ear or in the elbow fold, left for the time on the IFU, then read. It is looking for a reaction to the mix you are about to put on a scalp. It is not a personality quiz and it is not optional because they 'have been coming here for years' — regulars are the ones who sometimes react after a formula change.

PPD and related dyes are the usual concern. The CTPA has published consumer and salon-facing material on hair colour allergies for years. Manufacturers print the method on the box for a reason. If you invent a quicker method, you are off the IFU.

This is a working explanation for people who do the job, not legal, insurance or medical advice. Read your own policy, your local authority, and the current wording from the bodies named. Glow records what you set. It does not decide the rule and it does not claim a salon is compliant.

Typical numbers — and why they are typical, not law

A very common UK starting point is: test at least 48 hours before colour, bleach or toner; treat a pass as current for around six months; retest when the brand or the family of product changes, or when they have been away longer than the window. Some insurers write 24 hours. Some write every colour service. Some want a fresh test after certain medications or after a known reaction.

There is no single Act of Parliament that says '48 hours and six months'. There is a stack of insurance schedules, NHBF-style good-practice talk, and manufacturer IFUs that converge on those numbers. If your schedule says something else, your schedule wins.

What the file has to show if they react

Who was tested. When. With which product and batch. Where it was put. What you saw at the read. Whether they signed to say they understood a pass is not a guarantee. Whether the colour they then had was the same family. Whether anyone asked about previous colour and about black henna — the CTPA has been clear that a previous black henna tattoo is a red flag for PPD sensitisation. That question has its own page: Black henna and hair colour.

A salon that 'always tests' but cannot show this client's card will look, to an insurer, like a salon that did not test. Memory is not a record.

Cut-and-finish is not colour

A good rule is per service family. Cut, blow-dry, treatments that never touch oxidative dye do not need an allergy alert test just because the same client sometimes has colour. Putting a blanket test on every wet cut trains people to lie on the form so they can have a trim.

Colour, bleach, toner, some bleached-then-toned jobs, and any service the IFU says to test — those carry the rule. If you are unsure about a gloss or a direct dye, read the box and the schedule, do not guess at the basin.

Insurers, NHBF and the FHA

Insurers are not shy: a reaction claim without a documented allergy alert test is often declined. The size of those claims is why. A scalp reaction that becomes a lost-earnings or scarring argument is not a small complaint.

The NHBF speaks for a lot of UK salons on standards and on talking to insurers. The FHA (Federation of Holistic Therapists) is more therapy-sided but the same habit applies: written records, dated, signed. None of those bodies have asked Glow to speak for them. Cite them as places you go to read, not as a badge on your booking page.

How to run the test without losing the afternoon

Book it as its own short appointment, or pair it with a cut that is already in the diary, 48 hours before the colour. Do not do it as a walk-in on the Saturday they wanted the bleach, unless your written policy allows that and you are prepared to move the colour.

Tell them on the booking page how long a test lasts. People who can see the rule argue with it less at the desk. If the test has expired, they book a new one. If they refuse, you refuse the colour. That conversation is easier when the computer has already said no.

What a bad week looks like without a date

Friday night a client messages that their scalp blistered after Thursday's bleach. You remember testing her 'at some point'. The card drawer has three slips with her first name and no year. The tube is already in the bin. The insurer asks for the test. You cannot produce it. That is the week this page is for.

The other version of the week: the booking shows a skin test on 12 March, a pass, the same brand family, a signature, and Thursday's batch. You still have an unwell client. You still call the insurer. You have a file. Those are different weeks.

None of this makes a reaction smaller. It makes the difference between 'we have no idea' and 'here is what we did'. Hairdressers who have been through a claim do not need that explained twice.

What Glow does with this

Hair categories on Glow use the words skin test and allergy alert test. The default is 48 hours' lead and six months' validity. Cut-and-finish can stay unblocked. Colour will not book online if the test has lapsed. Batches and the signature sit on the visit.

See Glow for hair salons and pricing. Glow will not write to your insurer. It will show what you recorded.

A note on language in mixed salons: if the same building also does lashes, that category can still say patch test. The hair category should not. Clients who have both a tint and a colour in a year should see the right noun on each booking. Mixing the words on a hair form is how people think you copied a lash app. You did not. You used the words the colour houses already print.