Biological Risk Engineering Handbook: Infection Control and Decontamination - Chapter 12 pot

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© 2003 BY CRC PRESS LLC CHAPTER 12 Biocides Martha J. Boss and Dennis W. Day CONTENTS 12.1 Non-Public Health Products 12.2 Public Health Products 12.2.1 Sterilizers (Sporicides) 12.2.2 Disinfectants 12.3 Antiseptics and Germicides 12.4 Sanitizers 12.4.1 Food-Contact Sanitizers 12.4.2 Non-Food-Contact Sanitizers 12.5 Decontamination Methods and Biocides 12.6 Acids and Alkalizers 12.6.1 Acids 12.6.2 Alkalizers 12.7 Alcohols 12.8 Chloramines 12.9 Ammonia and Quaternary Ammonia 12.10 Dyes 12.10.1 Formaldehyde 12.10.2 Ethylene Oxide 12.10.3 Beta-Propriolactone 12.10.4 Glutaraldehyde 12.11 Halogens 12.11.1 Iodine 12.11.2 Iodophors 12.11.3 Chlorine 12.12 Heavy Metals 12.13 Oxidizers 12.13.1 Ozone 12.14 Phenols 12.15 Soaps and Synthetic Detergents 12.15.1 Anionic Detergents 12.15.2 Cationic Detergents © 2003 BY CRC PRESS LLC 12.15.3 Nonionic Detergents 12.16 Irradiation or Ultraviolet Light 12.17 Desiccants 12.18 Low Temperatures 12.19 Equipment Decontamination or Disposal References and Resources This chapter discusses the rationale for choosing or specifying various biocides, the known additional risks imposed through the use of biocides, the testing required to prove biocide claims, and the limitations of Material Safety Data Sheets (MSDS) in providing hazard communication information. Antimicrobial agents are substances or mixtures of substances used to destroy or suppress the growth of harmful microorganisms, whether bacteria, viruses, or fungi, on inanimate objects and surfaces. Antimicrobial products contain about 300 different active ingredients and are marketed in several formulations: sprays, liquids, concentrated powders, and gases. More than 8000 antimicrobial products are currently registered with the U.S. Environmental Protection Agency (EPA) and sold in the marketplace. Nearly 50% of antimicrobial products are registered to control infectious microorganisms in hospitals and other healthcare environments. However, public health antimicrobial products tend to be low-volume products and thus constitute less than 5% of the estimated total market for antimicrobial products. Antimicrobial products are divided into two categories based on the type of microbial pest against which the product works. 12.1 NON-PUBLIC HEALTH PRODUCTS Non-public health products are used to control the growth of algae, odor-causing bacteria, bacteria that cause spoilage, deterioration or fouling of materials, and microorganisms infectious only to animals. This general category includes products used in cooling towers, jet fuel, paints, and treatments for textile and paper products. 12.2 PUBLIC HEALTH PRODUCTS Public health products are intended to control microorganisms infectious to humans in any inanimate environment. The more commonly used public health antimicrobial products include the following: • Bactericidals, to kill bacteria • Bactericides, to kill bacteria • Bacteriostats, to inhibit the growth of bacterial cells • Cidal agents, to kill cells • Fungicides, to kill fungi • Static agents, to inhibit the growth of cells (without killing them) 12.2.1 Sterilizers (Sporicides) Sterilization is complete destruction or elimination of all viable organisms (in or on an object being sterilized). An object is either completely sterile or not sterile, nothing in between. Sterilization is used to destroy or eliminate all forms of microbial life, including fungi, viruses, and all forms of bacteria and their spores. Spores are considered to be the most difficult form © 2003 BY CRC PRESS LLC of microorganism to destroy; therefore, the EPA considers the term sporicide to be synonymous with sterilizer. Sterilization is critical to infection control and is widely used in hospitals on medical and surgical instruments and equipment. Gaseous and dry-heat sterilizers are used primarily for sterilization of medical instruments. Liquid sterilants are primarily used for delicate instruments that cannot withstand high temperatures and gases. Chemical sterilizers include low- temperature gas (ethylene oxide) and liquid chemical sterilants. Following are features of the heat sterilization methods. 12.2.1.1 Heat For heat sterilization, consider the type of heat, the application interval, and the temperature. Endospores of bacteria are considered the most thermoduric of all cells. The destruction of test or indicator endospores guarantees sterility. 12.2.1.2 Incineration (> 500°F) Incineration literally burns organisms from equipment or from the interior of vessels. Nonporous and nonflammable objects that can survive the heat levels needed to destroy contained organisms can be incinerated. Incineration can also be used to destroy organisms in wastes, in that the integrity of the remaining materials for future use is not an issue. 12.2.1.3 Water Boiling (100°C) Boiling water at 100°C for 30 minutes can be effective in killing microbial pathogens and vegetative forms of bacteria. To kill endospores, and therefore sterilize the solution, very long or intermittent boiling is required. Intermittent boiling is defined as boiling for three 30-minute intervals, followed by periods of cooling. 12.2.1.4 Autoclaving (121°C) Autoclaving is another name for pressure cooking. A temperature of 121°C for 15 minutes at a pressure of 15 lb/in. 2 sterilizes. The effective temperature (121°C) must be maintained for the full 15 minutes. Some materials will be destroyed at these temperatures through melting. 12.2.1.5 Dry Heat/Hot-Air Oven (160 and 170°C) These ovens maintain a temperature of 160°C for 2 hours or 170°C for 1 hour. The ovens can be used for objects that will not melt and must remain dry. 12.2.1.6 Pasteurization Pasteurization is the use of mild heat to reduce the number of microorganisms in a product or food. In the case of pasteurization of milk, the time and temperature depend on killing potential pathogens that are transmitted in milk (e.g., Staphylococcus, Streptococcus, Brucella abortus, and Mycobacterium tuberculosis). For pasteurization of milk, the following methods can be used: • Batch method: 63°C for 30 minutes kills most vegetative bacterial cells, including pathogens such as Streptococcus, Staphylococcus, and Mycobacterium tuberculosis. • Flash method: 71°C for 15 seconds has an effect on bacterial cells similar to the batch method; for milk, this method is more conducive to industry and has fewer undesirable effects on quality or taste. © 2003 BY CRC PRESS LLC 12.2.2 Disinfectants Disinfectants kill microorganisms, but not necessarily their spores, and are not safe for appli- cation to living tissues. They are used on hard inanimate surfaces and objects to destroy or irreversibly inactivate infectious fungi and bacteria but not spores. Examples include chlorine, hypochlorites, chlorine compounds, lye, copper sulfate, and quaternary ammonium compounds. Disinfectant products are divided into two major types: hospital and general use. 12.2.2.1 Hospital Disinfectants Hospital disinfectants are the most critical to infection control and are used on medical and dental instruments, floors, walls, bed linens, toilet seats, and other surfaces. 12.2.2.2 General Use Disinfectants General use disinfectants are the major type of products used in households, swimming pools, and water purifiers. Disinfectants and antiseptics are distinguished on the basis of whether they are safe for application to mucous membranes, and safety often depends on the concentration of the compound. For example, sodium hypochlorite (chlorine), as added to water, is safe for drinking, but Clorox ® , an excellent disinfectant, is not safe to drink. 12.3 ANTISEPTICS AND GERMICIDES Antiseptics and germicides are used to prevent infection and decay by inhibiting the growth of microorganisms. Because these products are used in or on living humans or animals, they are considered drugs and are thus approved and regulated by the Food and Drug Administration (FDA). Antimicrobial pesticides, such as disinfectants and sanitizers, are pesticides that are intended to: • Disinfect, sanitize, reduce, or mitigate growth or development of microbiological organisms • Protect inanimate objects, such as floors and walls, cabinets, toilets, industrial processes or systems, paints, metalworking fluids, wood supports, surfaces water, or other chemical substances These products protect users from contamination, fouling, or deterioration caused by bacteria, viruses, fungi, protozoa, algae, or slime. Antimicrobial pesticides, as a regulatory category, do not include certain pesticides intended for food use but do encompass pesticides with a wide array of other uses. Antimicrobials are especially important because many are public health pesticides. They help to control microorganisms (viruses, bacteria, and other microorganisms) that can cause human disease. Antimicrobial public health pesticides are used as disinfectants in medical settings. Proper use of these disinfectants is an important part of infection control activities employed by hospitals and other medical establishments. Disinfectants and sanitizers contain toxic substances. The ability of chemicals in other household products used for cleaning to cause health effects varies greatly, from those with no known health effect to those that are highly toxic. Read and follow label instructions carefully, and provide fresh air by opening windows and doors. If it is safe for you to use electricity and the home is dry, use fans both during and after the use of disinfecting, cleaning, and sanitizing products. Be careful about mixing household cleaners and disinfectants together (check labels for cautions on this). Mixing certain types of products can produce toxic fumes and result in injury and even death. Antiseptics are microbiocidal agents harmless enough to be applied to the skin and mucous membrane, but they should not be taken internally. Examples include mercurials, silver nitrate, iodine solution, alcohols, and detergents. © 2003 BY CRC PRESS LLC 12.4 SANITIZERS Used to reduce, but not necessarily eliminate, microorganisms from the inanimate environment to levels considered safe as determined by public health codes or regulations. 12.4.1 Food-Contact Sanitizers Food-contact sanitizers include rinses for such surfaces as dishes and cooking utensils and for equipment and utensils found in dairies, food-processing plants, and eating and drinking establish - ments. These products are important because they are used at sites where food products are stored and consumed. 12.4.2 Non-Food-Contact Sanitizers Non-food-contact surface sanitizers include carpet sanitizers, air sanitizers, laundry additives, and in-tank toilet bowl sanitizers. 12.5 DECONTAMINATION METHODS AND BIOCIDES Decontamination methods may be very similar to those used to abate asbestos or lead. The main difference is the use of biocides, which are chemicals designed to kill life. Thus, at concen - trated levels, biocides are a danger to workers. Manufacturers’ instructions must be carefully followed. When researching which biocides to use and the concentrations required, the following should be considered: • Type of biological contamination: Does the manufacturer have data showing that the product is effective against the biological contaminants at the current contamination level? Dwell time required after application of the biocide should be calculated in terms of biocide effectiveness. • Presence of electrical wiring or ventilation equipment that could be corroded by biocides • Flammability hazards posed by the biocides and their application methods • General building ventilation, workplace zoning, and level of occupancy of the building • Ability to isolate or shut down the heating, ventilation, and air conditioning (HVAC) system • Usage in false plenums, ductwork, flexible ductwork, horizontal plenums, and ventilation hoods • Usage in furnace, boiler, or other combustion chamber areas • Usage on condensers, face and bypass systems, and evaporative coils • Usage in cooling towers, sumps, liquid-filled plumbing lines and vessels, misters • Usage in humidifiers, swamp coolers, and sprinkler systems • Slip, trip, and fall potential when used on flooring or polyethylene sheeting • Dermal hazard potential if personal protective equipment (PPE) is breached • Respiratory hazards for the chosen application methods • Waste disposal requirements These and other questions regarding biocides and decontamination methods must be approached on a site-specific basis. Issues regarding potential adverse effects on carpets, porous materials, heirlooms, antique finishes, and other real property not slated for disposal must also be considered. Biocides come in several forms: • Acids or bases that are pH altering • Chlorines, bromines, or iodines • Chlorine dioxide • Hydrogen peroxide • Hypochlorite granules © 2003 BY CRC PRESS LLC • Alcohols • Phenols such as the active ingredients in Lysol  • Sulfur compounds • Quaternary ammonia • Stabilized chemical mixes • Ozone gases Soaps have limited biocide properties and function primarily to remove biological contamination from surfaces. Some liquid soaps have added biocides to enhance their bacterial biocide effect. Bar soaps should not be used on decontamination sites, as without sufficient drying the bar and surrounding liquids may harbor biological contaminants. Ozone gas treatments used alone or in combination with ultraviolet light treatment have shown success in eliminating airborne spores. These treatments, however, must be repeated several times to cover all spore-release cycles follow - ing initial decontamination events. Material Safety Data Sheets for biocides may discuss hazards based on the assumption that the biocides will be used for surface applications only. Manufacturers should be consulted whenever fogging, concentrated soaking applications, high-pressure delivery systems, or usage within confined areas is anticipated. Steam cleaning without the use of biocide washes or rinses is usually not effective and may make the situation worse. The core of the stream is very hot and perhaps produces steam, but the peripheries of the core often do not retain sufficient heat to kill biological contaminants. Dry and wet vacuuming, if used in a cleaning cycle, may aerosolize additional biological fragments, spores, and particulates to which biological contaminant are attached. Thus, vacuuming and sweeping may require additional personal and area protection for workers and building inhab - itants. In general, dry removal without prior treatment of areas with biocides should be carefully evaluated in terms of increased hazards. The choice of biological decontamination methods must be determined by an Occupational Safety and Health Administration (OSHA)-competent person and should be reflected in contract documents and resulting plans. Due to their spent biocide content, biocides and materials treated with biocides may be considered hazardous wastes. During the development of MSDS, manufacturers are required to determine disposal options for spent chemical, but materials laced with the chemical are not included in MSDS devel - opment. In determining appropriate disposal and labeling requirements, the following general regu- latory requirements should be considered: 29 CFR 1910.1200 (Hazard Communication) and equivalent requirements in 29 CFR 1926; the Resource Conservation and Recovery Act (RCRA), in regard to storage, treatment, and disposal of wastes; and Department of Transportation (DOT) requirements for labeling, marking, placarding, and transportation protocols on public byways. 12.6 ACIDS AND ALKALIZERS Acids and alkalizers cause changes in the microenvironment of the microbes. 12.6.1 Acids If the microenvironment is maintained at about pH 3, organisms begin to die off. The longer this lower pH is maintained, the greater the die off. Acids are used in food preservation techniques. 12.6.2 Alkalizers Alkalizers work against Gram-positive cocci, rods, spore-formers, and some viruses. Mycobac- terium species are resistant to alkali © 2003 BY CRC PRESS LLC 12.7 ALCOHOLS Alcohols are effective killers of vegetative bacteria and fungi but are not effective against endospores and most viruses. They are used to enhance the effectiveness of other chemical agents and work by denaturing proteins and dissolving lipids. The effectiveness of various alcohols increases with increasing molecular weight; unfortunately, their negative impact on skin also increases. Ethanol (50–70%) and isopropanol (50–70%) denature proteins and solubilize lipids and are used as antiseptics on skin. 12.8 CHLORAMINES Chloramines are produced by, and ultimately are a combination of, chlorine and ammonia. Chloramines are slow to volatilize, release the chlorine over long periods of time, are effective in contact with organic matter, and are used in root canal surgery and for general wound disinfection. Halazone is an example of a chloramine used for emergency disinfection of water. Chloramine is used in the treatment of public water supplies to reduce tastes and odors, the by-products of disinfection such as trihalomethanes (THMs), and the level of THMs in the water. The principal disadvantages of chloramines are that they are far weaker and slower acting disinfectants than chlorine and are especially weak for inactivating certain viruses. When chloramine is used as the principal disinfectant, ammonia is added at a point downstream from the initial chlorine application so that microorganisms, including viruses, will be exposed to the free chlorine for a short period before the chloramine is formed. Hospitals and kidney dialysis centers must be alerted when chloramines are used for water supply disinfection. Cases of chloram - ine-induced hemolytic anemia in patients have been reported when their dialysis water was not appropriately treated. Otherwise, no ill effects associated with the ingestion of chloraminated drinking water are documented. Chloramines can be removed from water with very low flow rates (5 to 10 minutes contact time) through shell-base activated carbon, followed by mineral zeolite media for residual ammonia adsorption. 12.9 AMMONIA AND QUATERNARY AMMONIA Ammonia and quaternary ammonia are detergents (quaternary ammonium compounds) that disrupt cell membranes and are used as skin antiseptics and disinfectants. 12.10 DYES Dyes are used primarily in selective and differential media and can be used intravenously and as pills or applied to the skin in liquid form. Some dyes may be strong mutagenic agents, and the actions of some are unclear. When used as gaseous chemosterilizers, these disinfectant aerosol particles should be between 1 and 5 µm in size to be most effective: 12.10.1 Formaldehyde Formaldehyde (8%), or formalin (40%), reacts with NH 2 , SH, and COOH groups to disinfect by killing endospores. Formaldehyde is toxic to humans, works best in dry environment (better penetration), and crystallizes at room temperature. © 2003 BY CRC PRESS LLC 12.10.2 Ethylene Oxide Ethylene oxide is volatile, flammable, and offers good penetration. Ethylene oxide gas is an alkylating agent used to sterilize heat-sensitive objects such as rubber and plastics. 12.10.3 Beta-Propriolactone Beta-propriolactone is nonflammable, and is more antimicrobial and less penetrating than ethylene oxide. 12.10.4 Glutaraldehyde Glutaraldehyde is effective at room temperature, and its microbial activity increases with heat. It is effective against certain viruses, endospores, and Mycobacterium species. It may irritate skin or eyes. Examples of glutaraldehyde include Sonacide  , Cidex  , and Metracide  . 12.11 HALOGENS Halogens include iodine, chlorine, bromine, and fluorine. The disinfectant usually recommended for mold removal is a solution of one part bleach to two parts water. Commercial disinfectants are also available through janitorial supply stores. Use a household or garden sprayer and spray all surfaces that have been touched by flood water or have been soaked by water from some other source. Use a brush or broom to force the solution into crevices. 12.11.1 Iodine Tincture of iodine (2% I 2 in 70% alcohol) inactivates proteins and is used as an antiseptic on skin. Iodine is one of the oldest (300 to 400 years) and most effective germicidal agents. It is a broad-spectrum bactericide and a good fungicide with some viricidal action. It will kill spores and is an excellent disinfectant that is effective against protozoa (amebas). It is only slightly soluble in water; iodine is available as a tincture dissolved in alcohol. Problems arise when the alcohol evaporates and the concentration of iodine increases, which can cause burning of skin. 12.11.2 Iodophors Iodophors are combinations of iodine and organic molecules (hydrocarbons). Iodophors work by inhibiting enzyme action and are more effective than iodine. They are nonirritating, good surfactants, and nonstaining. 12.11.3 Chlorine Chlorine (Cl 2 ) gas forms hypochlorous acid (HClO), a strong oxidizing agent, and is used to disinfect drinking water and as a general disinfectant. Chlorine is used as a gas dissolved in water or in combination with other chemicals. The chlorine mode of operation is not completely under - stood but appears to be a strong oxidizing agent as result of the following reaction: Cl 2 + H 2 O → HCl + HClO → HCl + [O] Hypochlorites are used domestically and industrially for disinfection. Hypochlorites were first advocated by Semmelweiss (1846–1848) to reduce incidence of childbed fever in hospitals, and © 2003 BY CRC PRESS LLC they have a broad spectrum of kill. NaOCl (sodium hypochlorite) is the active agent in Clorox  . Chlorine is a universal disinfectant that is active against all microorganisms, including bacterial spores. Potential applications for chlorine as a disinfectant include: • Work surfaces •Glassware • Fixed or portable equipment and cages • Liquids treated for discard • Before and after vivarium entry, as a footbath Many active chlorine compounds are available at various strengths; however, the most widely used for chemical disinfection is sodium hypochlorite. Household or laundry bleach is a solution of 5.25% (or 52,500 ppm) sodium hypochlorite. Note that a 10% or 1:10 dilution of bleach will result in a 0.525% or 5250-ppm solution of chlorine. The Centers for Disease Control and Prevention (CDC) recommends 500 ppm (1:100 dilution of household bleach) to 5000 ppm (1:10 dilution of bleach), depending on the amount of organic material present, to inactivate the human immunode - ficiency virus (HIV). The strength of chlorine to be used for disinfection must be clearly indicated when described in standard operating procedures. Chlorine solutions will gradually lose strength, so fresh solutions must be prepared frequently. Diluted solutions should be replaced after 24 hours. The stability of chlorine in solution is greatly affected by the following factors: • Chlorine concentration • Presence and concentration of catalysts such as copper or nickel • pH of the solution • Temperature of the solution • Presence of organic material • Ultraviolet irradiation The chlorine solution should have the following characteristics for maximum stability: • Low chlorine concentration • Absence or low content of catalysts such as nickel or copper • High alkalinity • Low temperature • Absence of organic materials Chlorine should be shielded from ultraviolet light by storage in the dark in closed containers. The following factors may or may not affect chlorine biocidal activity: • pH — Chlorine is more effective at a lower pH. • Temperature — An increase in temperature produces an increase in bactericidal activity. • Concentration — A fourfold increase of chlorine will result in a 50% reduction in killing time, and a twofold increase results in a 30% reduction in killing time. • Organic material — Organic material will consume available chlorine. If the organic material contains proteins, the reaction with chlorine will form chloramines that will have some antibacterial activity. Loss due to organic materials is more significant if minute amounts of chlorine are used. Footbaths are frequently contaminated with organic material and may require more frequent changing than the 24 hours previously stated. • Hardness — Hardness of the water does not have a slowing effect on the antibacterial action of sodium hypochlorite. • Addition of ammonia or amino compounds — Addition of ammonia and nitrogen compounds will slow the bactericidal action of chlorine. © 2003 BY CRC PRESS LLC Other available active chlorine sources include liquid chlorine, chlorine dioxide, inorganic chloram- ines, organic chloramines, and halazone. Chlorine combines with protein and rapidly decreases in concentration when protein is present. This property gives rise to swimming pool odor which is often mistaken for the odor of chlorine. In actuality, that characteristic swimming pool odor indicates that the chlorine in the water has combined with organic contaminants and is off-gassing from the pool water. The organic source may be contamination in the pool (e.g., perspiration, urine, feces). Other natural non-protein materials and plastics and cationic detergents may also inactivate chlorine. Chlorine is a strong oxidizing agent that is corrosive to metals and should not be used on the metal parts of machines that are subject to stress when in use. Do not autoclave chlorine solutions or materials treated with them, as the residual chlorine can vaporize resulting in an inhalation hazard. Do not use chlorine in combination with ammonia, acetylene, butadiene, butane, methane, propane or other petroleum gases, hydrogen, sodium carbide, benzene, finely divided metals, or turpentine. Chlorine may cause irritation to the eyes, skin, and lungs. Wear safety goggles, rubber gloves, aprons, or other protective clothing when handling undiluted solutions. 12.12 HEAVY METALS Heavy metals are the most ancient of antiseptics and disinfectants. Heavy metals were used by Egyptians, in the form of gold ointments and dust, and were often buried with the corpse or mummies to provide salves and ointments in the afterlife. Heavy metals have an oligodynamic (all encompassing) action and are extremely effective. They work because of the strong affinity of the metals to proteins. Metallic ions bind and adhere to the sulfhydryl groups in proteins, and enzymatic bindings are created. Stronger concentrations act as protein precipitants. Low concentrations have a subtle interference on the metabolism of the cell. Examples of heavy metal usage as disinfectants include the use of copper for ionizing water and to control algae. DaVinci and others added gold dust to ointments for wounds. Mercuric chloride inactivates proteins by reacting with sulfide groups and is used as a disin- fectant, although it occasionally is also used as an antiseptic on skin. Mercurials (inorganic mercury compounds) have a long history, with their heyday occurring during World War I. Mercurials were replaced by organic mercury compounds such as mercurochrome, methiolate, and metaphen. These compounds were used as skin antiseptics but their effects are reversed when they are washed off. Due to the toxic effects of mercury, these compounds are no longer recommended for first aid or skin disinfection. Silver nitrate (AgNO 3 ) precipitates proteins and is used as a general antiseptic and in the eyes of newborns. Silver, as a 1% silver nitrate solution (Argyrol), has been used as an antiseptic and in the eyes of newborn, although this practice has been largely replaced by the use of antibiotics. Zinc is used in combination with chlorine compounds as a mouthwash and in other combinations is an effective fungicide. Organometallics (organically activated metals such as heavy metals or organic radicals such as alcohol) are effective against Gram-positive cocci, diphtheroids, spore- forming rods, tuberculosis, and similar organisms and may be effective against viruses. They are extremely effective against mycoses and have virtually no effectiveness against Gram-negative rods. Tributyltin is an example of an organometallic that also has deodorizing qualities. 12.13 OXIDIZERS Oxidizers supply boundless oxygen. In combination with mercurials, oxidizers have been used in wound cleaning. Examples include H 2 O 2 (hydrogen peroxide), KMnO 4 (potassium permangan- ate), and zinc peroxide. [...]... Table 12. 1 Ozone Health Effects and Standards Health Effects Potential risk of experiencing: Risk Factors Factors expected to increase risk and severity of health effects are: Health Standards The Food and Drug Administration (FDA) requires ozone output of indoor medical devices to be no more than 0.05 ppm Decreases in lung function Increase in ozone air concentration The Occupational Safety and Health... for Ozone and Related Photochemical Oxidants, EPA/600/P-93/004aF-cF, 3v, National Center for Environmental Assessment–RTP Office, U.S Environmental Protection Agency, Research Triangle Park, NC, (PB-185582, PB96–185590 and PB96–185608), NTIS, Springfield, VA, 1996a USEPA, Review of National Ambient Air Quality Standards for Ozone: Assessment of Scientific and Technical Information, EPA-452/R-96–007,... chlorine solution and sequential rinses Respirator filters and cartridges cannot be decontaminated and should not be used for more than one work day Storage of biologically contaminated respirator filters and cartridges may cause residual biological contaminants to amplify through reproduction Thus, if respirator filters and cartridges are worn on successive day, workers will be exposed over and over again... processes (Dunston and Spivak, 1997) While high concentrations of ozone in air may sometimes be appropriate in these circumstances, conditions should be sufficiently controlled to ensure that no person or pet becomes exposed Ozone can adversely affect indoor plants and damage materials such as rubber, electrical wire coatings and fabrics and artwork containing susceptible dyes and pigments 12. 14 PHENOLS... and documented as to reuse of pails, buckets, mops, handheld tools, polyethylene sheeting, and other equipment exposed to biocides Porous materials, such as fibrous booms and spill mats, cannot be decontaminated and should be disposed Vacuums, whether dry or wet, and negative air machines should be decontaminated in accordance with manufacturers’ recommendations © 2003 BY CRC PRESS LLC REFERENCES AND. .. N.C and Spivak, S.M., A preliminary investigation of the effects of ozone on post-fire volatile organic compounds, J Appl Fire Sci., 6(3), 231–242, 1997 Dyas, A., Boughton, B.J., and Das, B.C., Ozone killing action against bacterial and fungal species: microbiological testing of a domestic ozone generator, J Clin Pathol., 36, 1102–1104, 1983 Esswein, E.J and Boeniger, M.F., Effects of an ozone-generating... air-purifying device on reducing concentrations of formaldehyde in air, Appl Occup Environ Hygiene, 9(2), 139–146, 1994 Favero, M.S and Bond, W.W., Sterilization, disinfection, and antisepsis in the hospital, in Manual of Clinical Microbiology, American Society for Microbiology, Washington, D.C., 1991, pp 183–200 Foarde, K., van Osdell, D., and Steiber, R, Investigation of gas-phase ozone as a potential... skin After absorption, hexachlorophene enters the blood stream and ultimately causes neurological damage Newborns and the elderly, with less subcutaneous fat, are at greater risk for brain damage These compounds work by denaturing cell proteins, inactivating enzymes, and damaging cell membranes 12. 15 SOAPS AND SYNTHETIC DETERGENTS Soaps and synthetic detergents act by mechanical removal of contaminants... Shields, H.C., Potential reactions among indoor pollutants, Atmos Environ., 31(21), 3487–3495, 1997b Weschler, C.J., Shields, H.C., and Naik, D.V., Indoor ozone exposures, J Air Pollut Contr Assoc., 39 (12) , 1562–1568, 1989 Weschler, C.J., Brauer, M., and Koutrakis, P., Indoor ozone and nitrogen dioxide: a potential pathway to the generation of nitrate radicals, dinitrogen pentaoxide, and nitric acid... detergent is any surface-tension depressant (keeps organisms spread out) 12. 15.1 Anionic Detergents For anionic detergents, the negatively charged portion of the molecule is the active part These detergents are not considered broadbased germicides but may work against Gram-positive bacteria C12H25OSO3 attached to Na+ is a common formulation Examples are sodium laurel sulfate and Dreft 12. 15.2 Cationic Detergents . Antiseptics and Germicides 12. 4 Sanitizers 12. 4.1 Food-Contact Sanitizers 12. 4.2 Non-Food-Contact Sanitizers 12. 5 Decontamination Methods and Biocides 12. 6 Acids and Alkalizers 12. 6.1 Acids 12. 6.2. Halogens 12. 11.1 Iodine 12. 11.2 Iodophors 12. 11.3 Chlorine 12. 12 Heavy Metals 12. 13 Oxidizers 12. 13.1 Ozone 12. 14 Phenols 12. 15 Soaps and Synthetic Detergents 12. 15.1 Anionic Detergents 12. 15.2. Alkalizers 12. 7 Alcohols 12. 8 Chloramines 12. 9 Ammonia and Quaternary Ammonia 12. 10 Dyes 12. 10.1 Formaldehyde 12. 10.2 Ethylene Oxide 12. 10.3 Beta-Propriolactone 12. 10.4 Glutaraldehyde 12. 11

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  • Biological Risk Engineering Handbook: Infection Control and Decontamination

    • Table of Contents

    • Chapter 12: Biocides

      • 12.1 Non-Public Health Products

      • 12.2 Public Health Products

        • 12.2.1 Sterilizers (Sporicides)

          • 12.2.1.1 Heat

          • 12.2.1.2 Incineration (> 500°F)

          • 12.2.1.3 Water Boiling (100°C)

          • 12.2.1.4 Autoclaving (121°C)

          • 12.2.1.5 Dry Heat/Hot-Air Oven (160 and 170°C)

          • 12.2.1.6 Pasteurization

          • 12.2.2 Disinfectants

            • 12.2.2.1 Hospital Disinfectants

            • 12.2.2.2 General Use Disinfectants

            • 12.3 Antiseptics and Germicides

            • 12.4 Sanitizers

              • 12.4.1 Food-Contact Sanitizers

              • 12.4.2 Non-Food-Contact Sanitizers

              • 12.5 Decontamination Methods and Biocides

              • 12.6 Acids and Alkalizers

                • 12.6.1 Acids

                • 12.6.2 Alkalizers

                • 12.7 Alcohols

                • 12.8 Chloramines

                • 12.9 Ammonia and Quaternary Ammonia

                • 12.10 Dyes

                  • 12.10.1 Formaldehyde

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