Cosmetology License Exam Chemical Texture Services Syllabus

What is the difference between on-base, half-off-base, and off-base rod placement?

On-base (rod sits within its own base section, ~45° over-direction) gives volume; half-off-base gives less stress; off-base (rod sits below its base) gives the least volume and reduces scalp tension.

What are the two main types of permanent wave solutions classified by pH?

Alkaline (cold) waves and acid (true acid-balanced) waves.

What is the main active ingredient and pH characteristic of a true acid wave?

Glyceryl monothioglycolate (GMTG) is the reducing agent; true acid waves have a pH of about 4.5 to 7 and usually require heat (exothermic or with a dryer).

Why are alkaline waves preferred for resistant or hard-to-wave hair?

Their high pH swells the hair and processes faster at room temperature, producing strong, firm curls without added heat.

What is an exothermic wave?

A perm that creates an exothermic chemical reaction producing heat, which speeds processing; it has a separate activator added to the waving lotion.

What is an endothermic wave?

An acid-balanced perm that requires an outside heat source (typically a hood dryer) to process properly.

During perm processing, what physically forms the new curl shape while the bonds are broken?

The hair takes the shape of the rod (the size and shape of the curl is set physically), then bonds are re-formed by neutralizing in that new shape.

What is a test curl (preliminary test curl) and what does it tell the stylist?

Unwinding a rod 1.5 to 2 turns to check that a firm, S-shaped wave the size of the rod has formed — it indicates whether processing is complete.

What does overprocessing in a perm look like and what causes it?

Too many disulfide bonds are broken; hair becomes frizzy, weak, or breaks; curls may be tight at the scalp but the ends are damaged. Caused by leaving solution on too long or solution too strong for the hair.

What does underprocessing in a perm look like?

Too few bonds were broken, producing a weak, limp, or no curl; the wave relaxes quickly. Hair may be reprocessed if undamaged.

What is the purpose of neutralization (rebonding) in permanent waving?

To re-form (re-bond) the disulfide bonds in their new curled position and stop the action of the waving lotion, locking in the curl.

What chemical reaction is neutralization, and what does the neutralizer do chemically?

Oxidation — the neutralizer (an oxidizing agent) removes the hydrogen added by the waving lotion, allowing disulfide bonds to re-form.

What is the most common active ingredient in a perm neutralizer?

Hydrogen peroxide (sometimes sodium bromate).

What two steps must be done before applying neutralizer to a perm, and why?

Thoroughly rinse the waving lotion from the hair (often 5+ minutes) and blot/towel-dry each rod to remove excess water, so the neutralizer is not diluted and can work properly.

What is the main active ingredient in a 'lye' relaxer?

Sodium hydroxide.

What are the advantages and disadvantages of sodium hydroxide (lye) relaxers?

Advantages: fast, effective on coarse/resistant hair. Disadvantages: very high pH, can swell/damage hair and irritate scalp, so base cream and care are required.

What does 'lanthionization' refer to in hydroxide relaxing?

The permanent conversion of disulfide bonds into lanthionine bonds; this break is irreversible, which is why hydroxide and thio chemistry should never be combined.

What are the three main types of metal/ion no-lye relaxers?

Guanidine hydroxide, lithium hydroxide, and potassium/ammonium-based hydroxide relaxers (lithium and potassium are marketed as 'no-mix, no-lye').

How is a guanidine hydroxide (no-lye) relaxer mixed and how does it compare to lye relaxers?

It is mixed by combining calcium hydroxide (cream) with guanidine carbonate (activator). It is gentler on the scalp but can leave hair drier and may cause calcium buildup.

Why are 'no-lye' relaxers often recommended for sensitive scalps?

They have a slightly lower pH and are less irritating to the scalp than sodium hydroxide, reducing the chance of scalp burns.

What is the purpose of a strand test before a relaxer service?

To determine how the hair will react, the correct processing time, and the degree of straightening before applying product to the whole head.

What is a base cream (protective base) and where is it applied in a relaxer service?

An oily cream applied to the entire scalp (and sometimes hairline/ears) to protect the skin from the caustic relaxer chemical.

What is the difference between a 'base' and a 'no-base' relaxer?

A base relaxer requires applying protective base cream to the entire scalp before use; a no-base relaxer contains a built-in protective base that melts at body temperature, so only the hairline/ears are protected.

In what order is relaxer applied to virgin hair, and why?

Apply first to the most resistant area, usually 1/4 to 1/2 inch away from the scalp (where body heat and prior application speed processing), then work toward the ends, applying last near the scalp.

What does 'smoothing' accomplish during the relaxer application?

Gently working the relaxer through the hair (with fingers or comb back) to straighten the curl while the chemical is processing.

How is a hydroxide relaxer neutralized, and why is this step critical?

By rinsing thoroughly and using an acid-balanced neutralizing (normalizing) shampoo that lowers the pH back to normal and stops the relaxing action; failure to fully neutralize causes continued damage and breakage.

Why must hydroxide relaxers be rinsed with comfortably warm (not hot) water and rinsed completely?

To remove all caustic chemical from hair and scalp before neutralizing; residue continues to break bonds and burn the scalp.

What is a soft curl permanent (double process)?

A combination service that uses a thio relaxer to first soften/loosen the existing curl, then perm rods and thio waving lotion to form a larger, looser curl pattern.

Why can a soft curl perm use a thio relaxer with rods, but a hydroxide relaxer cannot be permed afterward?

Soft curl perms rely on thio (reduction/oxidation) chemistry, which is reversible and re-bondable; hydroxide relaxers permanently form lanthionine bonds that cannot be re-curled, so combining the two causes breakage.

What are the key elements of a client consultation before a chemical texture service?

Analyze hair type/condition/porosity/elasticity, review scalp condition, discuss desired result, check for prior chemical treatments and medications, and assess any contraindications.

What is the purpose of a release (consent) form for chemical services?

It documents that the client was informed of risks and gave consent; note that it informs the client but does not release the cosmetologist from legal responsibility for negligence.

What is a patch (predisposition) test and is it required before perms/relaxers?

A test applying a small amount of product to skin to check for allergic reaction; perms/relaxers generally don't require it (it's required for tints), but a strand test is essential.

What does a porosity test measure and how is it performed?

It measures the hair's ability to absorb moisture/chemicals; slide fingers from ends toward scalp — if hair feels rough/ruffles up, it is porous (overporous hair processes faster).

How does porosity affect chemical processing time?

More porous hair absorbs solution faster and processes more quickly (and may need milder product), while resistant/low-porosity hair needs more time or stronger product.

What does an elasticity test measure and what is normal?

The hair's ability to stretch and return; wet hair with good elasticity stretches about 50% of its length and returns. Low elasticity hair is weak and prone to breakage.

Why should you avoid chemical overlapping during a relaxer retouch?

Applying relaxer over previously relaxed hair re-processes it, causing weakness and breakage; apply only to the new growth.

What is the single most important rule when a client has had a hydroxide relaxer and wants a perm (or vice versa)?

Never apply thio and hydroxide chemistry to the same hair — the incompatible chemistry causes severe breakage. The chemically treated hair must be grown/cut out first.

What are common signs that hair has been over-processed and needs reconditioning?

Dry, brittle, weak, frizzy, overly porous hair with poor elasticity that may break easily.

How should over-processed hair be reconditioned?

Use deep-conditioning protein/moisturizing treatments to rebuild and strengthen the hair, avoid further chemical services, and cut off severely damaged ends; protein fills gaps while moisturizers restore softness.

Why is a protein (substantive) conditioner or filler sometimes used before a texture service on damaged hair?

To equalize porosity and temporarily strengthen weak areas so the chemical processes more evenly and reduces the risk of breakage.