Microbiological control

The relative microbiological control abiUty of typical halogens is as follows ... 

Antimicrobial efficacy is also affected by demand in the cooling water system, specifically demand exerted by ammonia. Chlorine reacts with ammonia to form chloramines, which are not as efficacious as hypochlorous acid or the hypochlorite ion in microbiological control. Bromine reacts with ammonia to form bromamines. Unlike chloramines, bromamines are unstable and reform hypobromous acid. 

For turbidity, color and microbiological control in surface water treatment filtration. Common variations of filtration are conventional, direct, slow sand, diatomaceous earth, and membranes. 

One of the reasons why it is important to remove suspended solids in water is that the particles can act as a source of food and housing for bacteria. Not only does this make microbiological control much harder but, high bacteria levels increase the fouling of distribution lines and especially heat transfer equipment that receive processed waters (for example, in one s household hot water heater). The removal of suspended contaminants enables chemical treatments to be at their primary jobs of scale and corrosion prevention and microbial control. 

Optional microbiological control of ambient-temperature systems. 

Any other documentation related to product quality, which is not mentioned elsewhere (e.g. microbiological controls on air and water). 

Akers M.J. Taylor C.J. (1990) Official methods of preservative evaluation and testing. In Guide to Microbiological Control in Pharmaceuticals (eds S.R Denyer R.M. Baird), pp. 292-303. Chichester Ellis Horwood. 

British Pharmacopoeia (1993) Appendix XVI A Test for Sterility, A180-A184. London HMSO. (3.4) Denyer S. Baird R. (eds) (1990) Guide to Microbiological Control in Pharmaceuticals. Chichester Ellis Horwood. (3)... 

Denyer S. Baird R. (eds) (1990) Guide to Microbiological Control in Pharmaceuticals. London Ellis Horwood. 

Y. Henis and 1. Chet, Microbiological control of plant pathogens. Advances in Applied Microbiology 79 85 (1975). 

Yost, W.H. Microbiological Control in Recirculating Water Systems Avoids Fouling, Oil and Gas Journal, Apr. 16, 1973, p. 107. 

Microbiological Control Environmental Toxicology Environmental and Pollution Modeling... 

This review comprises most of the presentations given at the RSC Industrial Affairs Division Speciality Chemicals Sector conference titled Speciality Chemicals in Mineral Processing held in Bath, UK in 2001. The papers presented here are not intended to represent a comprehensive review of the use of speciality chemicals in mineral processing but rather the intention is to highlight a significant advance in chemical use in each of a number of different mineral process unit operations. The book is divided into three sections (i) dispersion and flocculation, (ii) selective processing and (iii) microbiological control. Within each of these areas papers are presented that cover some of the most important recent research and developments from both academia and industry. 

The final section of the book is devoted to microbiological control of mineral slurries. The first paper by Duddridge explores the EC s recent Biological Products Directive and speculates on the challenges that this will create for biocide producers, formulators and mineral slurry processors. The final two papers by Gutherie and Martin both introduce new microbiological control regimes. 

Specifications for biological starting materials may need additional documentation on the source, origin, method of manufacture and controls applied, particularly microbiological controls. 

The frequency of sanitization derived from the trend analysis of the microbiological data should be used as the alert mechanism for maintenance. The frequency of sanitization should be established such that the system operates in a state of microbiological control and does not exceed alert levels. 

Maintenance of microbiological control and quality (reference FDA Guidance Section V, A to C)... 

Microbiological Control to Prevent Corrosion in Recirculating Water... 

This demand will reduce the amount of chlorine available for microbiological control and lead to slime growth, especially in the tower basin and water distribution system, with biofilms and under-deposit corrosion being common effects of this problem. 

In a similar vein, technical discussions in textbooks and papers, up to only a few years ago, tended to cover problems such as corrosion, carbonate scaling, and microbiological control as individual topics that were somehow unrelated to each other. Such discussions were often quite theoretical and had little in common with field practicalities and realities. 

Merely periodically varying the types of microbiocides employed or adding product more frequently is generally insufficient to provide a well-managed microbiological control program and is seldom an effective solution for biocorrosion control, and may unnecessarily increase chemical treatment costs. 

There is, unfortunately, no foolproof guide available for the selection and application of microbiocides that can realistically ensure continuous, effective microbiological control in different types of cooling systems and under various operating conditions. 

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