2. A conductor is any substance that easily transmits electricity. An insulator is a substance that does not easily transmitted electricity.
3. There are two types of electric current.
Direct current- A constant, even flowing current that travels in one direction only. This includes flashlights, cell phones, and cordless electric drills.
Alternating current- A rapid and interrupted current, flowing first in one direction and then in the opposite direction. Used in hairdryers and curling irons.
4. Volt: unit that measures pressure or force that pushes the flow of electrons forward through a conductor.
Amp: unit that measures the amount of an electric current (quantity of electrons flowing through a conductor).
Ohm: unit that measures the resistance of an electric current.
Watt: measurement of how much electric energy is being used in one second.
5. You should always look for the UL symbol on electrical devices because Underwriter's Laboratory certifies the safety of electrical appliances.
6. The four main modalities used in esthetics are
Galvanic- a constant and direct current, having a positive and negative pole, which produces chemical changes when it passes through tissues and fluids of the body.
Faradic- an alternating and interrupted current that produces a mechanical reaction without a chemical effect.
Sinusoidal- alternating current that produces mechanical contractions that tone the muscles.
Tesla high-frequency- a thermal or heat-producing current with a high rate of oscillation or vibration.
7. In galvanic current, the effects of the poles are as follows:
Positive- produces acidic reactions, closes the pores, soothes the nerves, decreases blood supply, contracts blood vessels, hardens and firms tissues.
Negative- produces alkaline reactions, open the pores, stimulates and irritates the nerves, increases blood supply, expands blood vessels, softens tissues.
8. Iontophoresis: The process of introducing water-soluble products into the skin with the use of electric current.
Desincrustation: A process which uses the negative pole to soften and emulsify grease deposits and blackheads in the hair follicles.
9. Some benefits of Tesla high-frequency current are:
- Stimulates blood circulation
- Improves glandular activity
- Increases elimination and absorption
- Increases metabolism
- Improves germicidal action
- Relieves congestion
10. Electromagnetic radiation is energy in the form of electromagnetic waves. Also called radiant energy because it carries, or radiates, energy through space on waves.
Visible light is the primary source of light used in facial and scalp treatments.
11. The five main types of light therapy are:
Ultraviolet- used to increase the elimination of waste products, improve the flow of blood and lymph, germicidal and antibacterial effect, produce vitamin D in the skin, and can be used to treat rickets, psoriasis, and acne.
Infrared- used to heat and relax the skin, dilate blood vessels and increase circulation, produce chemical changes, increase metabolism, increase production of perspiration and oil, deep penetration to relieve pain and sore muscles, and soothe nerves.
White light- used to relieve pain in the back of the neck and shoulders, produce some chemical and germicidal effects, and relax muscles.
Blue light- soothes nerves, improves acne, improves skin tone, provides some chemical and germicidal effects, used for mild cases of skin eruptions, produces little heat.
Red light- improves dry, scaly, and wrinkled skin, increases rate of collagen building, relaxes muscles, penetrates the deepest, and produces the most heat.
12. Exposure to ultraviolet rays must be carefully monitored because over exposure can cause skin damage, premature aging, and skin cancer.
13. The acronym laser stands for light amplification stimulation emission of radiation.