1057 Theory - Unit 203 - Hair Tests

1057 Theory - Unit 203 - Hair Tests

by Sara Seekings

​Porosity Test (Poor-os-itee)

​Done to determine how porous the hair is

​Checks the condition of the cuticle

​Should be done before carrying out the service.

Using the first finger and thumb, slowly run down the length of two or three hairs from point to root on dry hair.

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The cuticles should feel smooth, if they feed rough then the hair is damaged and porous.

​The service could cause damage to the hair structure and the hair may break off.

​Elasticity Test ( Ee-las-tis-i-tee)

​This is done to see if the hair can stretch and spring back to its natural length. It tests how much moisture there is in the hair structure. Checks the condition of the cortex.

​It should be done on wet hair before carrying out a service, and sometimes during and after chemical services.

​It's done by taking one or two hairs and gently stretching them and allowing them to return.

​It's expected that the hair will stretch (up to one third) and return. If the hair breaks when it's stretched, or doesn't return to it's natural length then you should be cautious, because any service could break the hair off.

​Skin Test

​This is done 48 hours before carrying out a colour service which contain para compounds (so that's all colours except temporary, some semi's and bleach)

​You should take a small amount of colour and place behind the ear or on the inside of the elbow and left to develop - ALWAYS have a look at the MFIs to check you are doing this test as the manufacturer recommends.

​Hopefully there will be no reaction and your client will be able to go ahead with the service - BUT if the client reports that the skin has become red and itchy or irritated, swollen or sore - they have had a positive reaction. If you continue to colour the hair the client could have an allergic reaction, such as an anaphylactic shock.

​Incompatibility Test (In-com-pat-i-bill-i-tee)

​We do this to check for the presence of metallic compounds - such as metallic salts that can be found in some hair dyes.

​You should do this before any chemical services if you think the products could be incompatible. You should cut a piece of the hair (from the back of the head) and put this in a plastic bowl with a solution of 6% hydrogen peroxide and some perm lotion at a ratio of 20:1 (this means 20 parts hydrogen peroxide and 1 part perm lotion)

​You should see no change to the hair in the bowl if the hair is ok, however if the hair contains metallic compounds then it could heat up, bubble, change colour or disintegrate all together!. If you don't do this before a service the hair will turn a funny colour, the hair will be damaged and could fall out!

​Para-phenylenediamine, also called PPD.

​This is the most common ingredient in hair colour that causes allergic reactions.

​Strand Test

​This is done to check development of colour or bleach, it's done during the service when the colour is developing.

​Using a piece of cotton wool, remove the colour from a few strands of hair to see the colour.

​If the colour has processed fully and evenly to the desired shade then it can be removed (follow MFIs), however if the colour hasn't developed to the shade you wish (bleach) and the condition is still good (elasticity test) you should allow it to develop further. (check every few minutes)

​If you remove a colour before it's developed properly the results will be patchy, uneven, and if using bleach - orange or yellow.

​Colour Test (also called Test Cutting)

​This is done to check if the colour you/your client has chosen is suitable or achievable. It's done before any colour or lightning process, and should be done by applying the target shade to a small section of hair (on or off the head) Allow the colour to develop following MFIs, rinse, dry and check the colour.

​The expected result is that the required colour is achieved; you would show this to your client and continue with the service. However if the results are not as expected you and your client would have to agree on an alternative. The hair could become weak and damaged, or the required colour results may not be achieved if you carry on.

​Pre-Perm Test Curl

​This is done prior to the perming service to find out the correct rod size to use, and the strength of the solution required.

​To do this wind with the chosen rod, apply the product, process and neutralise a small section at the back of the head.

​You will be able to see: if the curl is tight/loose enough; if the hair is still in good condition.

​By doing this test you can see if you need to use different sized rods or solution to achieve the results your client wants. If you don't do this, then the hair could be damaged, too curly, too loose, the skin could be sore and the client would be unsatisfied.

​Curl Development Test

During the perming service, you should use a timer to accurately time the development of the perm - based on MFIs, hair condition and temperature. Once you have reached the desired time you need to check that the perm has developed evenly throughout the head.

​Check in THREE places - unwind a perm rod and push the hair back towards the head to check if you can see a 'S' shape.

​If the curl has formed to the desired degree, begin the neutralising process. If the curl is weak you will need to allow the perm to develop further (you may need to apply more lotion) If you neutralise too soon the curl will be weak and will drop, however if you leave the lotion on too long the hair will be frizzy, dry and overdeveloped.

​It is VITAL that you CHECK and FOLLOW MFIs before carrying out any hair tests.

​You should also consider Legal Requirements in relation to hair tests. Don't skip the testing process - we do these to make sure that the results will be achievable, and the hair condition is not compromised.

​REMEMBER - it's your reputation on the line!

Multiple Choice

Which part of the hair structure is checked when doing a porosity test?

• Medulla

• Cuticle

• Cortex

• Follicle

Multiple Choice

How should you complete an elasticity test?

• Cut hair and place in a bowl with perm lotion and 20vol peroxide

• Take a few hairs and run fingers down from point to root

• Take one or two hairs, gently stretch and let return

• Place a small amount of hair on the inside of the elbow

Multiple Choice

A skin test must be done 48 hours before the colour?

• True

• False

Multiple Choice

A strand test is done to check the strength of the cortex?

• True

• False

Multiple Choice

Applying colour to a small section of hair, on or off the head, is an example of how to carry out which test?

• Porosity Test

• Incompatibility Test

• Colour Test

• Curl development Test

Multiple Choice

What is the compound that causes allergic reaction in colours?

• metallic salts

• hydrogen peroxide

• para-phenylenediamine

• ammonium thioglycolate

Multiple Choice

You are using bleach on cap highlights, what test should you to to check development?

• Skin test

• Colour test

• Porosity test

• Strand test

Multiple Choice

When should you perform a per-perm test curl?

• After the service

• Prior to the service

• During the service

Multiple Choice

Your client's hair turned a strange colour, became really hot or disintegrated when a colour was applied. What would say was present in the hair causing this?

• para-phenylenediamine

• metallic salts

• ammonia

• disulphide bonds