Microbiologic sampling surface

The T-sections were free from pitting and the inside surface was clean. The water samples and the corrosion products were analyzed for microbiological activity. The water contained significant amount of iron-reducing biological activity. 

Production equipment that cannot be sterilized must be sanitized and disinfected by an appropriate method. This can be done by use of biocides like alcohols (70%), hydrogen peroxide, or formaldehyde-based chemicals or a combination of these. These can either be used for surface disinfections by wiping or spraying or even better by use of gas or dry fog systems for application of the disinfectants. The effect of cleaning and sanitation should be monitored. Microbiological media contact plates can be used to test critical surfaces, as inside the hot cells or glove boxes. The test samples must then be handled and monitored as radioactive contaminated units. 

Surface sampling the exterior of finished products, as indicator sites, assembled from purportedly sterile components as they exit the process while still under aseptic conditions, may be a more efficacious method of estimating microbiologic contamination potential than invading the critical production site. This method allows sampling the most critical site adjacen to the product, and more sites may be non-invasively sampled over a longer interval. In addition, this method may substantially reduce the incidence of sampling-induced contamination. 

Conventional approaches to microbiological examination of specimens require that they be cultured to assess the total numbers of specific groups of microorganisms or to determine the presence or absence of particular named species. The majority of samples taken for examination contain mixtures of different species, so simple plating onto an agar surface may fail to detect an organism that is present at < 2% of the total viable population. Various enrichment culture techniques may therefore be deployed to detect trace numbers of particular pathogens, prior to confirmatory identification. 

To control sterility or cleanness in hospital environment microbiology methods, laborious and time consuming (24-120 h), are used at present. To accelerate and simplify the sterility or cleanness control on different surfaces we applied bioluminescent assay of total bacterial contamination (TBC). Since the most surfaces analyzed in hospital contained low number of bacteria, below the detection limit of ATP-reagent used, incubation of the samples in nutritive medium followed by filtration through special luminometric microcuvettes Filtravette was applied. 

Figure 1. Different patterns of biodegradation resulting from microbial adaptation. (A) Adaptation to p-nitrophenol in Lulu aquifer samples at 529 ng/mL, but not at 14 ng/mL (41). (B) Adaptation to the triazinone-ring of metribuzin, evidenced by an increasing mineralization rate over time in the surface soil, but not in the subsurface soils (351. (C) Adaptation to EPTC after long-term EPTC use (12). (Reproduced with permission from Ref. 12. 15, 43. Copyrights 1988, 1989, 1987 Weed Science Society of America, American Society of Agronomy, and American Society for Microbiology, respectively)...

Siderite is a common mineral in mires, where it is formed through microbiological reduction of iron oxides in the environment. This mechanism may explain its occurrence on artefacts that have lain exposed on the mire surface for a period of time. In these conditions they will be quickly covered by a layer of iron oxides, which will subsequently be reduced to siderite after being overgrown and embedded in an anoxic environment. However, for other artefacts (and modem samples) that have been placed directly under anoxic conditions the siderite must have formed directly from the metallic iron, and here it is still unclear exactly what cathodic reaction is responsible for the oxidation of iron. A Pourbaix diagram based on the actual soil conditions at Nydam is shown in Figure 8. The hatched area in the Pourbaix diagram demonstrates that the pH values found at Nydam are close to the lower limit for siderite stability, so the soil pH is monitored intensively to be sure that no acidification takes place. 

Cleanrooms and related areas should be monitored at planned intervals for microbiological contamination using one or more of air sampling, settle plates and surface sampling techniques and the results obtained used to determine action levels. 

Processing should be conducted in a deanroom suite, constructed and operated in accordance with the air cleanliness standards. In order to control the microbiological and particulate cleanliness of the various grades/dasses of operation, the areas should be monitored using various methods, e.g., volumetric air sampling, settle plates, surface sampling (swabs, contact plates). 

Areas should be frequently monitored microbiologically by means of settle plates, surface sampling, air sampling or other appropriate methods. The monitoring should be performed while normal production operations are in progress. Records should be retained and immediate remedial action taken as soon as results deviate significantly from those usually found in the area concerned. (See 9.11 and 9.12). 

Failure of Copper Pipe in a Sprinkler System Straight sections and T-sections were examined along with the analysis of water for corrosion products for microbiological activity. The straight sections of the pipe showed dark red and greenish spots on the surface (Fig. 5.48) through-wall pits were present in the red spots. The T-sections did not have red spots (Fig. 5.49), but one sample had a crack (Fig. 5.50). 

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