The main signs and symptoms are:
Dermatitis is not ‘catching’- it can’t be passed from one person to another. It can develop at any time, or not at all - everyone is different.
There are two types of contact dermatitis: irritant contact dermatitis & allergic contact dermatitis.
Irritant contact dermatitis can flare up after a few contacts with strong chemicals like bleach. More commonly it develops gradually through frequent wet working or working with milder chemicals like shampoo.
Allergic contact dermatitis can develop quickly after only a few contacts with a substance like shampoos or colours. Sometimes it can take months or even years for the allergy to develop. Once you are allergic, you are allergic for life and this could happen at any time, even if you have had no problems previously in your career.
With allergic contact dermatitis, the things you can become allergic to at work might well also be in things you use at home - like your shampoo, or your household cleaners. So if you become allergic to something in the salon it could well affect all aspects of your life.