Q: I am interested in ammonia-free hair dyes that are less harmful to the scalp than normal dyes. Which salons here have such dyes?

A: Most major haircare brands now stock ammonia-free hair colour options, so chances are most salons carrying major haircare brands will also carry ammonia-free dyes.

L'Oreal Professionnel, for instance, has a Richesse semi-permanent colour range that is ammonia-free. It will unveil an ammonia-free Inoa permanent colour range in June.

To find out which salons stock Richesse, call 6738-3113 or e-mail [email protected].

Redken's ammonia-free colour range is called Shades EQ. To find out which salons carry it, call 6233-0807 or e-mail [email protected].

Ammonia-free hair colour costs about the same as those that contain ammonia and most salons would typically charge about $95 onwards for a dye job using ammonia-free colour.

You could consider cheaper drugstore options such as L'Oreal Paris' DIY colour range, Casting. This ammonia-free dye is available at all major personal care stores and costs $18.90.

With the exception of the upcoming Inoa, current ammonia-free options tend to fall in the semi-permanent category, which means the colour has a roughly 60 per cent shorter shelf life compared to permanent colour.

If you are covering grey hair, or if your natural hair colour is quite light, such semi-permanent dyes will work pretty well, says veteran hairstylist Casey Chua. Other pluses for ammonia-free colour: It is less harsh on your hair and also does not stink like normal hair dyes.

However, if your natural colour is dark, hair colour that contains ammonia may well do a better job as the chemical helps to lighten hair and allows colour to penetrate deeper.

This article was first published in Urban, The Straits Times.