Autoclaving moist

Respirator parts Moist heat (autoclave) Moist heat (low- temperature steam, or hot water at 80°C) Sterilization Disinfection Sterilization by steam where possible Chemicals not recommended may be microbiplogically ineffective, may present hazard to patient safety by compromising the safety devices on the machine... 

SiOv can be applied to films such as PET, PP, nylon and PE. Ox usually lies between 1 and 2 (but excludes 2, i.e. Si02). Improvements in barrier properties are up to 120x for oxygen and 45xfor moisture, but severe creasing can cause a reduction. It has been shown that CPD coated SiOr. films will withstand autoclaving (moist heat) of 121°C, or perhaps above. 

Silica and Alumina. The manufacture of Pordand cement is predicated on the reaction of lime with siUca and alumina to form tricalcium sihcate [12168-85-3] and aluminate. However, under certain ambient conditions of compaction with sustained optimum moisture content, lime reacts very slowly to form complex mono- and dicalcium siUcates, ie, cementitious compounds (9,10). If such a moist, compact mixture of lime and siUca is subjected to steam and pressure in an autoclave, the lime—silica reaction is greatiy accelerated, and when sand and aggregate is added, materials of concrete-like hardness are produced. Limestone does not react with siUca and alumina under any circumstances, unless it is first calcined to lime, as in the case of hydrauhc lime or cement manufacture. 

Steam (qv) sterilization specifically means sterilization by moist heat. The process cannot be considered adequate without assurance that complete penetration of saturated steam takes place to all parts and surfaces of the load to be sterilized (Fig. 1). Steam sterilization at 100°C and atmospheric pressure is not considered effective. The process is invariably carried out under higher pressure in autoclaves using saturated steam. The temperature can be as low as 115°C, but is usually 121°C or higher. 

Moist heat (autoclaving) 121°Cfor ISmin 134°Cfor3min... 

Principles of the methods employed to sterilize pharmaceutical products are described in Chapter 20. The British Pharmacopoeia (1993) recommends autoclaving and filtration as suitable methods applicable to aqueous liquids, and dry heat for non-aqueous and dry sohd preparatiorrs. The choice is determined largely by the ability of the formulation and container to withstand the physical stresses apphed by moist heat... 

Syringes (glass) Syringes (glass), dismantled Dry heat Moist heat Sterilization Sterilization Dry heat using assembled syringes Autoclave not recommended difficulty with steam penetration unless plungers and barrels sterilized separately... 

When drug solutions and containers can withstand autoclaving conditions, this method is preferred to other sterilization methods because moist heat sterilizes quickly and inexpensively. However, judgment must be exercised and experiments run to ensure that the solution and container are permeable to steam. Oils and tightly closed containers, for example, are not normally sterilizable by steam. 

Heating moist Raney nickel alloy containing 20% aluminium in an autoclave under hydrogen caused the aluminium and water to interact explosively, generating 1 k bar pressure of hydrogen. 

Evidence for the microbiological degradation of 2,4-D ester in soils was based on the stimulation by warm, moist conditions and organic matter (19) a correlation between degradation rate and the numbers of aerobic soil bacteria (20) and inhibition when the soils were air-dried and autoclaved (iTT. Little information is available, however, on the nature of the degradation products. 

The medium is then sterilized to eliminate all living organisms in the vessel.,The most common method of sterilization is by moist heat (steam under pressure) in an autoclave. Generally, the autoclave is operated at approximately 15 psi at 121°C. The time of sterilization depends on the nature of the material, the type of container, and the volume. For example, test tubes of liquid media can be sterilized in 15 to 20 minutes at 121 °C. 

Heat is the most widely used means of sterilization, which can be employed for both liquid medium and heatable solid objects. It can be applied as dry or moist heat (steam). The moist heat is more effective than the dry heat, because the intrinsic heat resistance of vegetative bacterial cells is greatly increased in a completely dry state. As a result the death rate is much lower for the dry cells than for moist ones. The heat conduction in dry air is also less rapid than in steam. Therefore, dry heat is used only for the sterilization of glassware or heatable solid materials. By pressurizing a vessel, the steam temperature can be increased significantly above the boiling point of water. Laboratory autoclaves are commonly operated at a steam pressure of about 30 psia, which corresponds to 121°C. Even bacterial spores are rapidly killed at 121 °C. 

Medium for use in a process simulation test can be rendered sterile using either moist heat (autoclaving) or filtration. The method chosen depends on the availability of suitable equipment and the information desired from the study. 

Parenteral Drug Association. Moist Heat Sterilization in Autoclaves Cycle Development, Validation and Routine Operation. PDA technical report 1, revision, draft 11. Bethesda, MD, May 2001. 

PDA (2006), Technical Monograph 1, Industrial moist heat sterilization in autoclaves, draft 17. 

Curing conditions play an important role in the composite behavior, which has been attributed primarily to the influence of curing on the matrix properties. Two curing methods that are generally used in fiber cement composites are air/moist curing (normal pressure and temperature) and autoclave curing (high pressure and temperature). 

Under the usual autoclaving conditions, moist heat does not destroy pyrogens. For closures to be... 

It has long been known that endotoxins are thermostable in the presence of moist heat and that they are not appreciably destroyed by routine autoclaving processes. Early research showed that boiling was not completely effective. However, endotoxins can be destroyed by dry heat at temperatures above 180°C. In fact, dry heat is the method of choice for depyro-genating heat-resistant materials, such as glass and equipment. 

Moist-heat autoclaves operating with counterpressure are sterilizers capable of controlling the pressure of their sterilizing medium independently of its temperature. They are used essentially for the terminal sterilization of solutions. 

Moist heat offers the advantage of greater effectiveness at low temperatures. The thermal capacity of steam is much greater than that of hot air. Spores and vegetative forms of bacteria may be effectively destroyed in an autoclave employing steam (121°C) under pressure (ISpsig) for 20 min or (27psig at 132°C), for 3 min. The lag time to complete exposure of the material to be sterilized is important. 

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