Disinfection: Rendering pathogens harmless through the use of heat, antiseptics, antibacterial agents, etc.Disinfectants: Substances used on inanimate objects that destroy harmful microorganisms or inhibit their activity. Disinfectants are classed as complete, destroying SPORES as well as vegetative forms of microorganisms, or incomplete, destroying only vegetative forms of the organisms. They are distinguished from ANTISEPTICS, which are local anti-infective agents used on humans and other animals. (From Hawley's Condensed Chemical Dictionary, 11th ed)Sterilization: The destroying of all forms of life, especially microorganisms, by heat, chemical, or other means.Water Purification: Any of several processes in which undesirable impurities in water are removed or neutralized; for example, chlorination, filtration, primary treatment, ion exchange, and distillation. It includes treatment of WASTE WATER to provide potable and hygienic water in a controlled or closed environment as well as provision of public drinking water supplies.Chlorine: A greenish-yellow, diatomic gas that is a member of the halogen family of elements. It has the atomic symbol Cl, atomic number 17, and atomic weight 70.906. It is a powerful irritant that can cause fatal pulmonary edema. Chlorine is used in manufacturing, as a reagent in synthetic chemistry, for water purification, and in the production of chlorinated lime, which is used in fabric bleaching.Dental Disinfectants: Chemicals especially for use on instruments to destroy pathogenic organisms. (Boucher, Clinical Dental Terminology, 4th ed)Trihalomethanes: Methanes substituted with three halogen atoms, which may be the same or different.Chlorine Compounds: Inorganic compounds that contain chlorine as an integral part of the molecule.Hand Disinfection: The act of cleansing the hands with water or other liquid, with or without the inclusion of soap or other detergent, for the purpose of destroying infectious microorganisms.Equipment Contamination: The presence of an infectious agent on instruments, prostheses, or other inanimate articles.Water Supply: Means or process of supplying water (as for a community) usually including reservoirs, tunnels, and pipelines and often the watershed from which the water is ultimately drawn. (Webster, 3d ed)Sodium Hypochlorite: It is used as an oxidizing and bleaching agent and as a disinfectant. (From Grant & Hackh's Chemical Dictionary, 5th ed)Chloramines2-Propanol: An isomer of 1-PROPANOL. It is a colorless liquid having disinfectant properties. It is used in the manufacture of acetone and its derivatives and as a solvent. Topically, it is used as an antiseptic.Endoscopes: Instruments for the visual examination of interior structures of the body. There are rigid endoscopes and flexible fiberoptic endoscopes for various types of viewing in ENDOSCOPY.Soaps: Sodium or potassium salts of long chain fatty acids. These detergent substances are obtained by boiling natural oils or fats with caustic alkali. Sodium soaps are harder and are used as topical anti-infectives and vehicles in pills and liniments; potassium soaps are soft, used as vehicles for ointments and also as topical antimicrobials.Peracetic Acid: A liquid that functions as a strong oxidizing agent. It has an acrid odor and is used as a disinfectant.Iodophors: Complexes of iodine and non-ionic SURFACE-ACTIVE AGENTS acting as carrier and solubilizing agent for the iodine in water. Iodophors usually enhance bactericidal activity of iodine, reduce vapor pressure and odor, minimize staining, and allow wide dilution with water. (From Merck Index, 11th ed)Hexachlorophene: A chlorinated bisphenol antiseptic with a bacteriostatic action against Gram-positive organisms, but much less effective against Gram-negative organisms. It is mainly used in soaps and creams and is an ingredient of various preparations used for skin disorders. (From Martindale, The Extra Pharmacopoeia, 30th ed, p797)Povidone-Iodine: An iodinated polyvinyl polymer used as topical antiseptic in surgery and for skin and mucous membrane infections, also as aerosol. The iodine may be radiolabeled for research purposes.Water Microbiology: The presence of bacteria, viruses, and fungi in water. This term is not restricted to pathogenic organisms.Anti-Infective Agents, Local: Substances used on humans and other animals that destroy harmful microorganisms or inhibit their activity. They are distinguished from DISINFECTANTS, which are used on inanimate objects.Virus Inactivation: Inactivation of viruses by non-immune related techniques. They include extremes of pH, HEAT treatment, ultraviolet radiation, IONIZING RADIATION; DESICCATION; ANTISEPTICS; DISINFECTANTS; organic solvents, and DETERGENTS.Glutaral: One of the protein CROSS-LINKING REAGENTS that is used as a disinfectant for sterilization of heat-sensitive equipment and as a laboratory reagent, especially as a fixative.Chlorhexidine: A disinfectant and topical anti-infective agent used also as mouthwash to prevent oral plaque.Equipment Reuse: Further or repeated use of equipment, instruments, devices, or materials. It includes additional use regardless of the original intent of the producer as to disposability or durability. It does not include the repeated use of fluids or solutions.Halogenation: Covalent attachment of HALOGENS to other compounds.Fumigation: The application of smoke, vapor, or gas for the purpose of disinfecting or destroying pests or microorganisms.Steam: Water in its gaseous state. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Colony Count, Microbial: Enumeration by direct count of viable, isolated bacterial, archaeal, or fungal CELLS or SPORES capable of growth on solid CULTURE MEDIA. The method is used routinely by environmental microbiologists for quantifying organisms in AIR; FOOD; and WATER; by clinicians for measuring patients' microbial load; and in antimicrobial drug testing.Drinking Water: Water that is intended to be ingested.Decontamination: The removal of contaminating material, such as radioactive materials, biological materials, or CHEMICAL WARFARE AGENTS, from a person or object.Swimming PoolsWater Pollutants, Chemical: Chemical compounds which pollute the water of rivers, streams, lakes, the sea, reservoirs, or other bodies of water.Microbial Viability: Ability of a microbe to survive under given conditions. This can also be related to a colony's ability to replicate.Benzalkonium Compounds: A mixture of alkylbenzyldimethylammonium compounds. It is a bactericidal quaternary ammonium detergent used topically in medicaments, deodorants, mouthwashes, as a surgical antiseptic, and as a as preservative and emulsifier in drugs and cosmetics.Bromates: Negative ions or salts derived from bromic acid, HBrO3.Microwaves: That portion of the electromagnetic spectrum from the UHF (ultrahigh frequency) radio waves and extending into the INFRARED RAYS frequencies.Endoscopes, Gastrointestinal: Instruments for the visual examination of the interior of the gastrointestinal tract.Equipment and Supplies, Hospital: Any materials used in providing care specifically in the hospital.Dental Impression Materials: Substances used to create an impression, or negative reproduction, of the teeth and dental arches. These materials include dental plasters and cements, metallic oxide pastes, silicone base materials, or elastomeric materials.Hygiene: The science dealing with the establishment and maintenance of health in the individual and the group. It includes the conditions and practices conducive to health. (Webster, 3d ed)Maxillofacial Prosthesis: A prosthetic appliance for the replacement of areas of the maxilla, mandible, and face, missing as a result of deformity, disease, injury, or surgery. When the prosthesis replaces portions of the mandible only, it is referred to as MANDIBULAR PROSTHESIS.Contact Lens Solutions: Sterile solutions used to clean and disinfect contact lenses.Levivirus: A bacteriophage genus of the family LEVIVIRIDAE, whose viruses contain the short version of the genome and have a separate gene for cell lysis.Denture Rebasing: The process of refitting a denture by replacing the denture base material without changing the occlusal relations of the teeth. Rebasing may include adding to the denture base to compensate for resorptive changes to subjacent structures.Denture Bases: The part of a denture that overlies the soft tissue and supports the supplied teeth and is supported in turn by abutment teeth or the residual alveolar ridge. It is usually made of resins or metal or their combination.Infection Control: Programs of disease surveillance, generally within health care facilities, designed to investigate, prevent, and control the spread of infections and their causative microorganisms.Cystoscopes: Endoscopes for visual examination of the urinary bladder.Nitrosomonas europaea: The type species of the genus NITROSOMONAS, a gram-negative chemolithotroph that oxidizes ammonia to nitrite. It is found in soil, sewage, freshwater, and on building walls, and especially in polluted areas where air contains high levels of nitrogen compounds.Dental Equipment: The nonexpendable items used by the dentist or dental staff in the performance of professional duties. (From Boucher's Clinical Dental Terminology, 4th ed, p106)Bacteria: One of the three domains of life (the others being Eukarya and ARCHAEA), also called Eubacteria. They are unicellular prokaryotic microorganisms which generally possess rigid cell walls, multiply by cell division, and exhibit three principal forms: round or coccal, rodlike or bacillary, and spiral or spirochetal. Bacteria can be classified by their response to OXYGEN: aerobic, anaerobic, or facultatively anaerobic; by the mode by which they obtain their energy: chemotrophy (via chemical reaction) or PHOTOTROPHY (via light reaction); for chemotrophs by their source of chemical energy: CHEMOLITHOTROPHY (from inorganic compounds) or chemoorganotrophy (from organic compounds); and by their source for CARBON; NITROGEN; etc.; HETEROTROPHY (from organic sources) or AUTOTROPHY (from CARBON DIOXIDE). They can also be classified by whether or not they stain (based on the structure of their CELL WALLS) with CRYSTAL VIOLET dye: gram-negative or gram-positive.Ozone: The unstable triatomic form of oxygen, O3. It is a powerful oxidant that is produced for various chemical and industrial uses. Its production is also catalyzed in the ATMOSPHERE by ULTRAVIOLET RAY irradiation of oxygen or other ozone precursors such as VOLATILE ORGANIC COMPOUNDS and NITROGEN OXIDES. About 90% of the ozone in the atmosphere exists in the stratosphere (STRATOSPHERIC OZONE).Oxides: Binary compounds of oxygen containing the anion O(2-). The anion combines with metals to form alkaline oxides and non-metals to form acidic oxides.BiguanidesProsthesis Coloring: Coloring, shading, or tinting of prosthetic components, devices, and materials.Trichloroacetic Acid: A strong acid used as a protein precipitant in clinical chemistry and also as a caustic for removing warts.Bromine: A halogen with the atomic symbol Br, atomic number 36, and atomic weight 79.904. It is a volatile reddish-brown liquid that gives off suffocating vapors, is corrosive to the skin, and may cause severe gastroenteritis if ingested.Borates: Inorganic or organic salts and esters of boric acid.Sunlight: Irradiation directly from the sun.Air Microbiology: The presence of bacteria, viruses, and fungi in the air. This term is not restricted to pathogenic organisms.Stainless Steel: Stainless steel. A steel containing Ni, Cr, or both. It does not tarnish on exposure and is used in corrosive environments. (Grant & Hack's Chemical Dictionary, 5th ed)Gastroscopes: Endoscopes used for examining the interior of the stomach.Cross Infection: Any infection which a patient contracts in a health-care institution.Bronchoscopes: Endoscopes for the visualization of the interior of the bronchi.o-Phthalaldehyde: A reagent that forms fluorescent conjugation products with primary amines. It is used for the detection of many biogenic amines, peptides, and proteins in nanogram quantities in body fluids.1-Propanol: A colorless liquid made by oxidation of aliphatic hydrocarbons that is used as a solvent and chemical intermediate.Fomites: Inanimate objects that carry pathogenic microorganisms and thus can serve as the source of infection. Microorganisms typically survive on fomites for minutes or hours. Common fomites include CLOTHING, tissue paper, hairbrushes, and COOKING AND EATING UTENSILS.Steel: A tough, malleable, iron-based alloy containing up to, but no more than, two percent carbon and often other metals. It is used in medicine and dentistry in implants and instrumentation.Toilet Facilities: Facilities provided for human excretion, often with accompanying handwashing facilities.Mobile Applications: Computer programs or software installed on mobile electronic devices which support a wide range of functions and uses which include television, telephone, video, music, word processing, and Internet service.Denture Cleansers: Substances used to clean dentures; they are usually alkaline peroxides or hypochlorites, may contain enzymes and release oxygen. Use also for sonic action cleaners.Filtration: A process of separating particulate matter from a fluid, such as air or a liquid, by passing the fluid carrier through a medium that will not pass the particulates. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Elastomers: A generic term for all substances having the properties of stretching under tension, high tensile strength, retracting rapidly, and recovering their original dimensions fully. They are generally POLYMERS.Sanitary Engineering: A branch of engineering concerned with the design, construction, and maintenance of environmental facilities conducive to public health, such as water supply and waste disposal.Oocysts: Zygote-containing cysts of sporozoan protozoa. Further development in an oocyst produces small individual infective organisms called SPOROZOITES. Then, depending on the genus, the entire oocyst is called a sporocyst or the oocyst contains multiple sporocysts encapsulating the sporozoites.Contact Lenses, Hydrophilic: Soft, supple contact lenses made of plastic polymers which interact readily with water molecules. Many types are available, including continuous and extended-wear versions, which are gas-permeable and easily sterilized.Immersion: The placing of a body or a part thereof into a liquid.Sewage: Refuse liquid or waste matter carried off by sewers.Hardness Tests: A test to determine the relative hardness of a metal, mineral, or other material according to one of several scales, such as Brinell, Mohs, Rockwell, Vickers, or Shore. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Polymethyl Methacrylate: Polymerized methyl methacrylate monomers which are used as sheets, moulding, extrusion powders, surface coating resins, emulsion polymers, fibers, inks, and films (From International Labor Organization, 1983). This material is also used in tooth implants, bone cements, and hard corneal contact lenses.Housekeeping, Hospital: Hospital department which manages and provides the required housekeeping functions in all areas of the hospital.Denture, Complete, Upper: A complete denture replacing all the natural maxillary teeth and associated maxillary structures. It is completely supported by the oral tissue and underlying maxillary bone.Alcohols: Alkyl compounds containing a hydroxyl group. They are classified according to relation of the carbon atom: primary alcohols, R-CH2OH; secondary alcohols, R2-CHOH; tertiary alcohols, R3-COH. (From Grant & Hackh's Chemical Dictionary, 5th ed)Contact Lenses: Lenses designed to be worn on the front surface of the eyeball. (UMDNS, 1999)Infection Control, Dental: Efforts to prevent and control the spread of infections within dental health facilities or those involving provision of dental care.Caustics: Strong alkaline chemicals that destroy soft body tissues resulting in a deep, penetrating type of burn, in contrast to corrosives, that result in a more superficial type of damage via chemical means or inflammation. Caustics are usually hydroxides of light metals. SODIUM HYDROXIDE and potassium hydroxide are the most widely used caustic agents in industry. Medically, they have been used externally to remove diseased or dead tissues and destroy warts and small tumors. The accidental ingestion of products (household and industrial) containing caustic ingredients results in thousands of injuries per year.Resins, Synthetic: Polymers of high molecular weight which at some stage are capable of being molded and then harden to form useful components.Angioscopes: Endoscopes used for viewing the interior of blood vessels.Siloxanes: Silicon polymers that contain alternate silicon and oxygen atoms in linear or cyclic molecular structures.Environmental Microbiology: The study of microorganisms living in a variety of environments (air, soil, water, etc.) and their pathogenic relationship to other organisms including man.Cryptosporidium parvum: A species of parasitic protozoa that infects humans and most domestic mammals. Its oocysts measure five microns in diameter. These organisms exhibit alternating cycles of sexual and asexual reproduction.Biofilms: Encrustations, formed from microbes (bacteria, algae, fungi, plankton, or protozoa) embedding in extracellular polymers, that adhere to surfaces such as teeth (DENTAL DEPOSITS); PROSTHESES AND IMPLANTS; and catheters. Biofilms are prevented from forming by treating surfaces with DENTIFRICES; DISINFECTANTS; ANTI-INFECTIVE AGENTS; and antifouling agents.Silicone Elastomers: Polymers of silicone that are formed by crosslinking and treatment with amorphous silica to increase strength. They have properties similar to vulcanized natural rubber, in that they stretch under tension, retract rapidly, and fully recover to their original dimensions upon release. They are used in the encapsulation of surgical membranes and implants.Laundry Service, Hospital: Hospital department which administers all activities pertaining to the hospital laundry service.Funeral Rites: Those customs and ceremonies pertaining to the dead.Hydrocarbons, BrominatedAcanthamoeba Keratitis: Infection of the cornea by an ameboid protozoan which may cause corneal ulceration leading to blindness.Acanthamoeba: A genus of free-living soil amoebae that produces no flagellate stage. Its organisms are pathogens for several infections in humans and have been found in the eye, bone, brain, and respiratory tract.Ultraviolet Rays: That portion of the electromagnetic spectrum immediately below the visible range and extending into the x-ray frequencies. The longer wavelengths (near-UV or biotic or vital rays) are necessary for the endogenous synthesis of vitamin D and are also called antirachitic rays; the shorter, ionizing wavelengths (far-UV or abiotic or extravital rays) are viricidal, bactericidal, mutagenic, and carcinogenic and are used as disinfectants.Water Pollution: Contamination of bodies of water (such as LAKES; RIVERS; SEAS; and GROUNDWATER.)Equipment and Supplies: Expendable and nonexpendable equipment, supplies, apparatus, and instruments that are used in diagnostic, surgical, therapeutic, scientific, and experimental procedures.Dichloroacetic Acid: A derivative of ACETIC ACID that contains two CHLORINE atoms attached to its methyl group.Materials Testing: The testing of materials and devices, especially those used for PROSTHESES AND IMPLANTS; SUTURES; TISSUE ADHESIVES; etc., for hardness, strength, durability, safety, efficacy, and biocompatibility.CresolsQuaternary Ammonium Compounds: Derivatives of ammonium compounds, NH4+ Y-, in which all four of the hydrogens bonded to nitrogen have been replaced with hydrocarbyl groups. These are distinguished from IMINES which are RN=CR2.Norovirus: A genus in the family CALICIVIRIDAE, associated with epidemic GASTROENTERITIS in humans. The type species, NORWALK VIRUS, contains multiple strains.