Chapter 3 of 7~8% of exam

Electricity & Equipment

Salon professionals work with electricity every day — from a simple blow dryer to a galvanic facial machine. The California exam expects you to understand basic current types, the main electrotherapy modalities, how electromagnetic radiation (infrared and ultraviolet) is used on the skin, and the electrical safety rules that protect both the client and the licensee. This chapter covers those points in plain language and ties each one back to a relevant rule or industry standard.

AC vs DC current in the salon

Electricity flows as a stream of electrons through a conductor. There are two main forms used in a salon. Alternating current (AC) reverses direction many times per second; in the United States the wall outlet supplies AC at roughly 120 volts and 60 hertz. Most plug-in salon equipment — blow dryers, clippers, curling irons, lights, washing machines — runs on this AC supply. Direct current (DC) flows in one steady direction and is produced by batteries or by an AC-to-DC converter inside an appliance. DC is what galvanic electrotherapy devices use, because their chemical effects (such as iontophoresis and desincrustation) depend on a fixed positive and negative pole.

Standard US outlet supply
About 120 V, 60 Hz alternating current; powers most plug-in salon equipment.
National Electrical Code
DC for galvanic devices
Galvanic machines convert AC to DC internally so they can deliver a steady polarized current to the electrodes.
Industry standard

Faradic, galvanic, high-frequency, and microcurrent

Four electrical currents show up repeatedly in cosmetology curricula. Galvanic current is a steady DC. With a properly chosen polarity, it can push water-soluble products into the skin (iontophoresis, usually from the positive pole for acidic products) or saponify and soften surface sebum (desincrustation, from the negative pole using an alkaline solution). Faradic current is an interrupted or pulsating AC used historically to produce visible muscle contractions for facial toning. High-frequency current, also called Tesla current, is a rapidly oscillating AC delivered through a glass electrode. It generates a tiny amount of ozone and gentle heat at the surface, giving a mild germicidal and stimulating effect on oily or minor blemished skin. Microcurrent is an extremely low-level current measured in microamperes; it is generally sub-sensory and is used for gentle facial tissue stimulation, not for strong muscle contraction.

Galvanic polarity matters
Like charges repel: acidic (positively ionized) products are pushed in from the positive pole; alkaline desincrustation is performed from the negative pole.
Industry standard
High-frequency = mild surface effect
High-frequency current is not a deep medical treatment; it gives only a surface antiseptic and warming effect.
Industry standard
Microcurrent is sub-sensory
True microcurrent is so low that the client should not feel a sting or muscle jerk; strong contractions indicate the device or settings are wrong.
Industry standard

Infrared and ultraviolet radiation

Electromagnetic radiation appears on the exam mainly in two forms. Infrared (IR) radiation lies just past visible red light. Its longer wavelengths are absorbed as heat, which warms the skin, slightly dilates surface blood vessels, and helps creams and oils penetrate. Infrared lamps must be kept at a safe distance from the client, typically around 18 to 30 inches from the treatment area, and the practitioner should always confirm the client feels gentle warmth and not pain. Ultraviolet (UV) radiation lies just past visible violet light. Short-wavelength UV has germicidal properties but it also damages the eyes and burns the skin with even short direct exposure, so eye protection and limited exposure are required. UV cabinets in salons are storage aids only — they do not replace cleaning and disinfection of tools with an EPA-registered disinfectant.

Infrared safe distance
Keep the lamp roughly 18 to 30 inches from the treated area and adjust to client comfort; warmth, never pain.
Manufacturer instructions
UV is not a substitute for disinfection
A UV cabinet may help keep clean items dust-free in storage, but tools must still be cleaned and disinfected with an EPA-registered disinfectant.
16 CCR §979
Eye protection under UV
Both client and operator must wear UV-protective eye covering during any direct UV exposure.
Industry standard

Electrical safety in the salon

Most salon electrical incidents come from four root causes: water near outlets, overloaded circuits, damaged cords, and missing grounding. The defenses are simple and required by Cal/OSHA general electrical safety rules. A ground-fault circuit interrupter (GFCI) outlet is required in wet areas such as shampoo stations and near sinks; it senses very small current leakage to ground and trips within milliseconds, sharply lowering the risk of electrocution. A three-prong grounded plug connects the metal housing of an appliance to earth, so that an internal fault current flows safely to ground instead of through the user. Circuits should not be overloaded by stacking high-wattage tools onto a single power strip; this overheats wires and is a frequent cause of fires. Cords with cracked insulation or exposed wires must be removed from service immediately. If a plugged-in appliance ever falls into water, the first step is to cut the power at the breaker or unplug it at the outlet — never reach into the water.

GFCI in wet areas
GFCI protection is required near sinks, shampoo bowls, and other locations where water and electricity can meet.
8 CCR §2340
No daisy-chaining high loads
Do not run multiple high-wattage tools through a single power strip or extension cord; respect the circuit's amperage rating.
8 CCR §2340
Damaged cord = out of service
Tag and remove any tool with a frayed cord, cracked plug, or exposed wire until it is properly repaired or replaced.
8 CCR §2340
Power off before water rescue
If an energized appliance falls into water, cut the power at the breaker or unplug at the outlet before touching anything.
Cal/OSHA general electrical safety

Equipment care, sanitation, and maintenance

Electrical equipment must be cleaned and disinfected between clients just like any other multiuse tool. Non-electrical multiuse implements (combs, shears, clipper guards) are cleaned to remove debris and then fully immersed in an EPA-registered hospital disinfectant for the contact time on the label. Electrical tools that cannot be immersed — clippers, trimmers, hand-held wands, galvanic electrodes — must have hair and debris removed and have their blades and client-contact surfaces wiped or sprayed with an EPA-registered disinfectant according to the manufacturer's instructions; the motor housing is never submerged. Reusable metal electrodes used in galvanic, high-frequency, or microcurrent services must be cleaned and disinfected between clients. Salon owners are also expected to perform routine maintenance: check cords and plugs for damage, replace worn parts, keep filters and steamer reservoirs clean, and follow the manufacturer's care manual.

Tool sanitation between clients
Clean to remove debris, then disinfect with an EPA-registered disinfectant per label contact time before reuse.
16 CCR §979
Never immerse motorized tools
Clippers and other powered tools have their blades and surfaces disinfected per the manufacturer; the motor is not submerged.
16 CCR §979
Routine maintenance
Inspect cords, plugs, and equipment regularly; replace damaged parts and follow the manufacturer's care manual.
Cal/OSHA general electrical safety

Scope of practice with electrical devices

California limits which professionals may use which electrical devices. Cosmetologists and estheticians work only on the superficial skin and may use non-medical galvanic, high-frequency, and microcurrent devices for facial care. They may not use medical devices that penetrate beyond the surface of the skin, including ablative lasers, medical microneedling pens, and needle electrolysis for permanent hair removal. Before any electrotherapy service, screen the client for standard contraindications: pacemakers or other implanted electronic medical devices, pregnancy, epilepsy, metal implants in the treatment area, open or inflamed skin, and known sensitivity to electrical stimulation. Document the service and any reactions.

Esthetician scope is the skin's surface
Non-medical electrotherapy (galvanic, high-frequency, microcurrent) is allowed; medical lasers and needle electrolysis are not.
BPC §7316
Standard electrotherapy contraindications
Pacemakers and implanted electronic medical devices, pregnancy, epilepsy, metal implants in the treatment area, and broken skin are common reasons to refuse the service.
Industry standard
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