Glossary

Aerosol

Particles of respirable size generated by both humans and environmental sources that can remain viable and airborne for extended periods in the indoor environment.

Airborne Transmission

A means of spreading infection in which airborne droplet nuclei are inhaled by the susceptible host.

Allergic Contact Dermatitis

A type IV or delayed-hypersensitivity reaction resulting from contact with a chemical allergen, generally localized to the contact area.

Antiseptic

A germicide that is used on skin or living tissue for the purpose of inhibiting or destroying microorganisms.

Asepsis

A prevention from contamination with microorganisms.

Autoclave

An instrument for sterilization that uses moist heat under pressure.

Bacteria

Tiny one-celled organisms present throughout the environment that require a microscope to be seen.

Bioburden

The microbiological load (i.e. number of viable organisms in or on the object or surface) or organic material on a surface or object prior to decontamination, or sterilization, also known as “bioload” or “microbial load.”

Biofilm

A microbially-derived sessile community characterized by cells that are irreversibly attached to substratum or interface to each other, are embedded in a matrix of extracellular polymeric substances that they have produced, and exhibit an altered phenotype with respect to growth rate and gene transcription.

Biological Indicators

A device to monitor the sterilization process that consists of a standardized population of bacterial spores known to be resistant to the mode of sterilization being monitored.

Bloodborne Pathogens

Disease-producing microorganisms spread by contact with blood or other body fluids contaminated with blood from an infected person.

Carrier

An individual who harbors a disease agent and may transmit the infection without demonstrating apparent symptoms.

Chemical Indicators

A device used to monitor a sterilization process that changes color of form with exposure to one or more physical condition within a sterilizating chamber (e.g. temperature or steam).

Cleaning

The removal of visible soil or organic debris, either manually or mechanically, which results in a reduction in the number of microorganisms and the removal of organic matter, such as blood, tissue, and other biological material that may interfere with sterilization and disinfection.

Clinical Contact Surface

A surface contaminated from patient materials either from direct spray or spatter generated during dental procedures or by contact with dental healthcare personnel (DCHP)’s gloved hands.

Colony-forming Unit (cfu)

The minimum number of separable cells on the surface of or in semisolid agar medium that gives rise to a visible colony of progeny is on the order of tens of millions.

Critical

The category of medical devices or instruments that are introduced directly into the human body, either into or in contact with the bloodstream or normally sterile areas of the body (e.g. surgical instruments and scalpels).

Cross-contamination

Passage of microorganisms from one person or inanimate object to another.

Dental Healthcare Personnel (DHCP)

Refers to all paid and unpaid personnel in the dental healthcare setting who might be occupationally exposed to infectious materials.

Disinfectant

A chemical agent used on inanimate (i.e. nonliving) objects (e.g. floors, walls, and sinks) to destroy virtually all recognized pathogenic microorganisms, but not necessarily all microbial forms (e.g. bacterial endospores).

Droplets

Small particles of moisture (e.g. spatter) that may be generated when a person coughs or sneezes, or when water is converted to a fine mist by an aerator or shower head.

Dry-heat Sterilizer

An instrument for sterilization that uses heated air.

Emollients

Ingredients in hand-hygiene and hand-care products that add moisture to skin and reduce skin dryness.

Exposure Time (contact time)

The period of time during sterilization or disinfection process in which items are exposed to the sterilant or disinfectant at the parameters specified by the manufacturer.

Flash Sterilization

Process designed for the steam sterilization of unwrapped patient-care items for immediate use.

Hand Hygiene

A general term that applies to hand washing, antiseptic hand wash, antiseptic hand rub, and surgical hand antisepsis.

Healthcare-associated Infection

Any infection associated with a medical or surgical intervention.

High-level Disinfectant

A liquid chemical germicide registered by the FDA used in the disinfection process for critical and semicritical patient-care devices that inactivates vegetative bacteria, mycobacteria, fungi, and viruses, but not necessarily high numbers of bacterial spores.

Housekeeping Surface

Environmental surfaces (e.g. floors, walls, ceilings, and tabletops) that are not involved in direct delivery of patient care in healthcare facilities.

Instrument Washer

An automated device designed to clean medical and dental instruments.

Intermediate-level Disinfectant

A liquid chemical germicide registered by the EPA as a hospital disinfectant and with a label claim of potency as a tuberculocidal.

Irritation contact Dermatitis

The development of dry, itchy, irritated areas on the skin, which can result from frequent hand washing and gloving as well as exposure to chemicals.

Low-level Disinfectant

A liquid chemical germicide registered with the EPA as a hospital disinfectant.

Mechanical Indicator

Devices (e.g. gauges, meter, display, and printout) that display an element of the sterilization process (e.g. time, temperature, and pressure).

Noncritical

The category of medical items or surfaces that carry the least risk of disease transmission.

Opportunistic Infection

Infection caused by normally nonpathogenic microorganisms in a host whose resistance has been decreased or compromised.

Personal protective Equipment

Specialized clothing or equipment (e.g. gloves, masks, protective eyewear, and gowns) worn by an employee for protection against a hazard.

Resident Flora

Species of microorganisms that are always present on or in the body and are not easily removed by mechanical friction.

Retraction

The entry of oral fluids and microorganisms into water lines through negative water pressure.

Semicritical

The category of medical devices or instruments (e.g. mirror and amalgam condenser) that come into contact with mucous membranes and do not ordinarily penetrate body surfaces.

Single-use Disposable Items

A device intended to be used on one patient and then discarded appropriately.

Standard Precautions

Universal precautions were based on concept that all blood and body fluids that might be contaminated with blood should be treated as infections because patients with bloodborne infections can be asymptomatic or unaware they are infected.

Steam Sterilization

A sterilization process that uses saturated steam under pressure, for a specified exposure time and at a specified temperature, as the sterilizating agent.

Sterilization

The destruction or removal of all forms of life, with particular reference to microbial organisms.

Surface Barrier

Material that prevents the penetration of microorganisms, particulates, and fluids.

Surface-active agents that reduce surface tension. The help cleaning by loosening, emulsifying, and holding soil in suspension, which can thSurfactantsen be more readily rinsed away.

Transient flora

Microorganisms that may be present in or on the body under certain conditions and for certain lengths of time; they are easier to remove by mechanical friction than resident flora.

Ultrasonic Cleaner

A device that uses waves of acoustic energy (a process known as “cavitation”) to loosen and break up debris on instruments.

Wicking

Absorption of a liquid by capillary action along a thread or through material (e.g. the enhanced penetration of liquids through undetected holes in a glove).