Clean room conditions

Special environment needed (controlled temperature, clean-room conditions, absence of drafts, etc.)... 

The precision of the procedures under clean room conditions is shown in Table 1.6. 

The finished product is essentially sterile and if kept in a germ-free environment will be protected from spoilage. Some manufacturers handle the finished product in clean room conditions to enhance the shelf life. 

Downstream processing is normally undertaken under clean room conditions, with the final steps (e.g. sterile filtration and aseptic filling into final product containers) being undertaken under Grade A laminar flow conditions (Figure 3.18). 

Sn, Sb)02/Mica Sn(0,F)2/Mica electrically conductive conductive flooring, antistatic packaging materials, light colored primed plastic surfaces which can be electrostatically painted in further coating process, light colored conducting surfaces in clean room conditions for dust reduction [5.235]... 

Surface cleanliness is dominated by external contaminants such as airborne debris, scratches, etc. The size range of these contaminants is typically from submicron to tens of microns, both laterally and vertically. Polyester film is not manufactured under clean-room conditions and typically rolls of film are slit to size - dust is present or generated in these processes. These external contaminants are the major cause of surface related issues in down stream processing, but the bulk of these contaminants can be removed by some form of surface cleaning. 

In demanding applications, for example barriers for OLED displays, control of polymer smoothness and cleanliness by the routes mentioned above may not be sufficient. In such circumstances it is necessary to lay down a further coating under clean-room conditions which acts both as a planarizing coating and as a hard coat to prevent scratching on subsequent processing. This has been discussed elsewhere [6, 12, 13]. 

Production of good phosphors requires rigorous attention to synthesis or activation conditions. Careful control of activator concentrations, usually measured in parts per million, is essential. Multiple activators may be necessary to achieve the desired color, brightness, response or decay times. Virtually umneasurable, trace amounts of unwanted substances may have such severe deleterious effects on phosphor performance that the materials are usually produced under clean room conditions rivaling those used in the production of silicon based integrated circuits. 

Recovery (To verify cleanup time) All classes 24 months Test to establish time that a clean room takes to return from a contaminated condition to the specified clean room condition. This should not take more than 15 min. In accordance with ISO 14644-3 Annex B13 ... 

Specially purified APT (by multiple-step liquid extraction of selected, very pure batches under clean-room conditions) for the production of 4N and 6N tungsten sputter targets shows a much lower impurity content (Table 5.8). 

FIGURE 5.38. Ultrahigh-purity tungsten improvement in purity from 1988 to 1994 (target data) production takes place under clean room conditions [5.96]. 

In general, it is important to maintain clean room conditions throughout the production steps. 

Films (2 mil) were cast/cured under clean room conditions and dried prior to test. 

Important other applications of zeolites in this area include CO2 removal in the breathing atmosphere in space, and recycling of wastewater. Recently the NASA conducted research on the removal of gas components under ultra clean room conditions in satellite systems, where zeolites can reduce the oulgassing rate inside of instruments and absorb molecules without producing additional particles by themselves. 

Samples must neither be contaminated nor destabilized during storage and sample handling. Clean room conditions and precleaned storage containers, vials, etc. must be used throughout. Sample preparation... 

Exploration of /rg/kg or ng/kg levels of Cr requires many precautions (Versieck and Cornells, 1989). One of the primary concerns is that for clean room conditions. Belgian atmospheric aerosols contain 37 mg /kg Cr particulate matter, with a range of 8.8 - 150 mg/kg. Good analytical practice requires a fall-out below 1 / g/m. day in the working area. The use of a laminar flow hood, if possible a class 100 one, may offer an adequate solution at a modest price. 

Other investigators reported pinhole defect density data that scale roughly with the inverse of the square of the film thickness, which can be derived from dynamic arguments, as was shown in Eq. (11.20). Spinodal decomposition dominates the nucleation process under clean room conditions, while particle nuclea-tion increases in higher aerosol concentration environments. ... 

A list and associated description of the key attributes of the platform needs to be included. Attributes should be defined to document platform components sufficiently. These elements include hardware or equipment sets being used as well as necessary software algorithms. Elements also include what incoming materials are used on the process. Incoming materials may be from internal or external suppliers. When environmental controls are necessary, such as clean-room conditions, that also should be included. Also, items related to carrying out the process, such as methods, skills, and process conditions, should be summarized. 

This technique is not restricted to UHV, and it can be used in atmosphere or in clean room conditions. 

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