Windows control measures

Figure 4.41. Schematic diagram of cell for temperature- and atmosphere-controlled measurements using DRIFTS accessory shown In Fig. 4.25 (1) cell cover (38.1 x 21 x 3.2 mm) (2) window (16x2 mm) (3) cell assembly (38.1 x 21 x 29.2 mm) (4) cartridge heater (12.7 X 38.1 mm) (5) thermocouple (6) gas Inlet (0 = 6.35 mm) (7) gas outlet (0 = 6.35 mm). Reprinted, by permission, from B. Li and R. D. Gonzalez, > pp/. Spectrosc. 52, 1488-1491 (1998), p. 1489, Fig. 2. Copyright 1998 Society for Applied Spectroscopy.

Priority should be given to keeping arsonists out, especially when the premises are not occupied. Attention must be paid to primary control measures like the siting and security of windows, doors, locking mechanisms, fences and gates. 

The disadvantage of the two-phase contacting principle is related to the technical expenditure of realizing phase separation throughout the complete reactor passage. Special measures have to be taken to prevent phase inter-mixing. Also, this has to be controlled during the process. Hence inspection windows are essential (for the first prototype they may be eliminated later). 

An industrial standard method has been developed to test the lightfastness of polymers in accelerated test equipment [103]. The apparatus consists of a quartz-xenon tube with a special optical filter between the light source and the specimen to produce light that resembles window glass-filtered daylight [104], Samples are mounted at a specific distance from the arc and are supported on a frame which revolves around the arc 1 to 5 times per minute for uniform exposure. A blower unit in the base provides a flow of air which makes it possible to maintain a black panel temperature of 45°C, measured by a black panel thermometer which is positioned at level with the samples. A black panel unit consists of a bimetallic thermometer mounted on a steel frame. Both faces of the frame plate and also the stem of the thermometer are coated with a heat-resistant glossy black enamel. The relative humidity level in the exposure cabinet is closely controlled. 

Table 12.9-8 summarizes the results of field test conducted at the Home. The measurements were taken on two successive days with the windows open. Air samples taken next to the open window was used as control. Air samples taken at the middle of the room was assumed to represent the conditions of the room. The data shows that Prototype Unit was able to keep the airborne bacteria level in the room reasonable low compared to outside. Also, the Prototype Unit displays on average 52 % reduction per pass which is within the performance specification. 

Electrochemical measurements were performed in an electrochemical cell equipped with quartz windows which fit into the sample compartment of a Cary 14 spectrometer. The cell (CHjCN, 0.1N TEAP vs S.C.E.) employed three electrode (Pt auxiliary electrode) potentiostatic control. A Tacussell PRT Potentiostat and PAR model 175 signal generator were used for the measurements. 

Ideally the air will be introduced under controlled conditions of pressure and flow to provide for maximum dilution benefits. Because it is difficult, if not impossible, to measure or calculate the exhaust rate through doors, windows, leaks, and so on, it is desirable to allow for 10 percent more air to be supplied than the assumed exhaust. 

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