Adverse conditions

Small size, ruggedness, simple cabling and the ability to operate the equipment under adverse conditions in the field has also been design goals. The system should also conform with the regulations necessary for the CE-marking (i. e. standards and directives for EMC, Electrical Safety and Machine Safety). 

A measurement of particle moisture content will normally be taken at the exit of the dryer. This allows the process operators to make such adjustments as may be needed to maintain moisture within the desired range. Various instmments are used, none of which are entirely satisfactory, and periodic hand samples are used in some mills. Considering the importance of moisture sensing and control at the dryers, it is unfortunate that a truly efficient, consistent, and accurate sensing system is not yet available to the industry. The primary reasons for the difficulty of measuring moisture at the dryer exit are the extreme and adverse conditions of heat, dust, and moisture present at this location. 

When the surface conditions are acidic or the ambient humidity is low enough to affect the cure significantly, a surface accelerator may be used to promote the reaction. Available from most manufacturers, these basic solutions may be dip, wipe, or spray appHed. Recentiy, new additive chemistry has been developed that accelerates the cure under adverse conditions without the need for a separate accelerator. 

The acacia trees produce gum arable only under adverse conditions, lack of moisture, poor nutrition, and hot temperatures. Gum arable is produced at wounded surfaces of the acacia trees. The wounds are generally produced deUberately in cultivated trees by stripping bark during the dry season. The gum is collected by hand over a period of several weeks with average yields of 250 grams per tree per year. Cmde exudates are hand sorted and exported before processing and milling to various specifications. 

Sufficient numbers of control animals should be employed. The use of such controls allows a determination of normal values for features monitored ki the study and background kicidence of pathology ki the population studied detection of the onset of adverse conditions, eg, infection, which are unrelated to, and detrimental to, the conduct of the study and deviation of monitored features between controls and exposed animals, which may kidicate a treatmentrelated effect. 

Bismuth. Bismuth 2-ethyIhexanoate [72877-97-5] is an auxiliary drier that has been promoted for drying under adverse conditions. Like rare earths, in some coatings it is reported to give better results than zirconium at low temperature and high humidity. 

Under adverse conditions, certain microorganisms produce spores that germinate upon return to a favorable environment. Spores are a particularly stable form or state of bacteria that may survive diyness and temperature extremes. Some microorganisms form spores at a stage in their normal life cycle. 

Vacuum is finally judged to be the best medium to quench the arc plasma and interrupt a circuit undci the most adverse conditions. Figure 19,24 gives cross-sectional views of one pole of a vacuum circuit breaker and a typiciil construction of the arcing contacts and Figure... 

Microclimate suit A suit worn to protect an operator who is working m adverse conditions of either heat or cold. 

Tolerance The ability of a person to withstand adverse conditions of air quality, infectious agents, noise, vibration, or light without showing signs of infection or disease. 

Analyses are types of calculations but may be comparative studies, predictions, and estimations. Examples are stress analysis, reliability analysis, hazard analysis. Analyses are often performed to detect whether the design has any inherent modes of failure and to predict the probability of occurrence. The analyses assist in design improvement and the prevention of failure, hazard, deterioration, and other adverse conditions. Analyses may need to be conducted as the end-use conditions may not be reproducible in the factory. Assumptions may need to be made about the interfaces, the environment, the actions of users, etc. and analysis of such conditions assists in determining characteristics as well as verifying the inherent characteristics. (See also in Part 2 Chapter 14 under Detecting design weaknesses.)... 

Segregation is another important requirement and not only for nonconforming product as specified in clause 4.13. Segregation is vital in many industries where products can only be positively identified by their containers. It is also important to prevent possible mixing or exposure to adverse conditions or cross-contamination. Examples where segregation makes sense are ... 

In a process disturbance, the suddenness of the onset of the event will also play a significant role in human performance. This category refers to the time required for the process symptom to develop to the extent that it becomes detectable by the workers. If the s3unptom develops gradually, this leaves some scope for the workers to switch to a high mode of alertness. This allows them to develop an adequate mental model (see Chapter 2) of the process state. If an adverse condition develops extremely slowly it may not be detected by workers, particularly if its development spans more than one shift. 

Oil Muds. Oil-base muds can be used effectively to minimize the corrosion-related problems in drilling operations. These fluids are composed of a continuous oil phase in which water is emulsified. The performance of oil-base mud is very competitive with that of water-base muds, and is superior under some adverse conditions. However, as pointed out earlier, they are only used in special cases due to their high costs and environmental restrictions. Nevertheless, they are the most effective method to avoid corrosion-related problems. 

Adverse conditions with down draft - the down draft mixes with the products of combustion and diluted products enter the room for the brief period that the downdraft persists. The draft in the primary flue (and hence the performance of the appliance) is unaffected. 

Adverse conditions with up draft - the additional draft in the secondary flue causes excess air to be pulled through the diverter from the room. The baffle plate prevents the draft in the primary flue from being affected. 

Engineering standards Engineering standards can be utilized to estimate jobs when data is available and applies to the work to be performed. Standards provide an average time to complete a job, but special situations or adverse conditions are not considered. 

Coatings consisting of a mixture of equal parts of cadmium and tin are particularly suitable for the protection of steel fasteners in contact with aluminium in aircraft structures where electrochemical corrosive attack is prone to occur under adverse conditions. The protection afforded is... 

The effect of the finely cracked chromium layer is to equalise the anode and cathode areas more nearly, so that corrosion of the nickel under the chromium takes place more slowly than it would at larger, isolated cracks. Moreover, the corrosion proceeds laterally along the nickel surface and not in depth as is the case with conventional chromium hence failure of the coating under adverse conditions is less likely to occur. 

Surging or priming is the phenomena of wildly fluctuating and spouting BW levels as a result of poor operational or water chemistry conditions. Adverse conditions include ... 

The formation of a magnetite film, although highly desirable, is itself a form of corrosion. The effective protection of boiler surfaces requires the proper development of an adherent, nonporous, self-limited, and stable film. Under adverse conditions, however, such as when... 

Further stresses may be caused by the continued mechanical operation of the boiler under adverse conditions, leading to intergranular... 

As discussed in the introduction, boiler water (BW) treatment programs enable the waterside chemistry of boilers and their associated systems to be controlled within certain agreed upon and relevant parameters and specifications. They provide a countermeasure against a wide range of adverse conditions that may strive to develop and hinder efficient boiler operation or cause serious damage. 

For all risk factors and their combinations we will use both — routine and specially designed approaches to risk management with due account of new combinations of these factors. The proposed approach will allow to develop strategy of preventive intervention into risk management of the cohorts who working or resident in ecologically adverse conditions to use of... 

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