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Air sample bags

Air sample bags are convenient for sampling gases and vapors in which the analyte concentration is weU above the detection limits of the measuring system... [Pg.717]

Sample bag A. bag made from an inert polymer such as Teflon, complete with a fitting for connecting to an air-sampling pump. [Pg.1474]

Figure 1 Schematic diagrams of (a) stainless steel air sampling canister and (b) Tedlar bag... Figure 1 Schematic diagrams of (a) stainless steel air sampling canister and (b) Tedlar bag...
Samples of odorous air for olfactometric analysis are usually collected into a sample bag and transported to a laboratory for analysis. A sample bag may be placed in a container, and the bag is gradually filled with odorous air when air is removed from the gap between the container and the bag using a vacuum pump. [Pg.181]

The Netherlands Organization of Applied Scientific Research (TNO) carried out a comparative study with Teflon-FEP-bags. Ratios between the dynamic and static method ranged from 0.7 to 1.1 after a storage time of 24 hours (7). These Teflon-bags can be used several times. Normally the sample size is 50 to 100 litres but for ambient air samples of 1600 litres are sometimes necessary. [Pg.77]

The largest problem turned out to be the temperature differences between outlet air (85-220 C) and outdoor temperatures (0-15 C), causing condensation. The dew point of the outlet air was calculated, and experiments were carried out with dilution of the outlet air to prevent condensation in the sampling bags. Condensation was prevented by diluting the outlet air 5-150 times with diy, purified N2 gas. [Pg.92]

The olfactometer was calibrated using C02, as the odorous gas, diluted in air to 10000 ppm by volume, and contained in a 30 1 Tedlar bag (Fig. 5) (7). C02-free oxygen was used as the diluting gas. The C02 concentration was was sufficiently low to avoid significantly altering the density of the odorous air. The bag was connected by silicon rubber tubing to the rotameter inlets and the diluted gas mixture was sampled via a tube placed inside the nose-piece and analysed by an infra-red gas analyser, with an accuracy of greater than 1% (Fig. 5). [Pg.139]

The recommended standard method evolved is therefore as follows. The apparatus consists of flowmeters, two 1 1 glass cylinders in series and an odour sampling bag of Tedlar , connected with PTFE tubing as shown in Fig. 1. The air used is oil- and odour-free and preferably from a compressed air cylinder. The air stream splits in two so that the diy air mixes with the humid air that has passed through the sludge, so as to prevent condensation in the odour sampling bag. [Pg.148]

During some of the weeks, in Hoogvliet air samples were collected in order to make a direct comparison between immission concentration and experienced annoyance. The sampling was done by the Division for Nutrition and Food Research TNO Zeist. The samples were collected by a mobile unit of this institute during the same hour in which the panels made their measurements. Fourty teflon bags of 40 liters each were filled at three locations in such a way that all bags contained equal amounts from all three... [Pg.158]

Exhaled air Collection of whole breath into a sampling bag collected sample pulled through a Tenax cartridge GC/Electrolytic conductivity 13 ng on cartridge 63 13 Joetal. 1990 > z > 1 K H... [Pg.224]

The second approach laboratory analysis of air and/or soil samples (note the air sample can be obtained by gas samphng bag, filter, sorbent, and wet-contaminant collection methods). [Pg.94]

Two final examples of the sensitivity and general applicability of the FTIR gas analysis technique are illustrated in Fig. 8. Trace (A) shows the spectrum obtained from an ultra-air filled 70 liter sampling bag into which had been injected, 18 hours previously, 4.8 microliters of TDI, toluene diisocyanate. On the basis of the single feature at 2273 cm l, it is estimated that 50 ppb TDI could be detected. The lower Trace (B), shows the spectrum of nickel carbonyl. This highly toxic but unstable gas was found to decay rapidly at ppm concentrations in ultra air (50% lifetime 15 minutes). Calibration of its spectrum was established by recording successive spectra at ten minute intervals and by attributing the increase in carbon monoxide concentration (calibration known) to an equivalent but four times slower decrease in nickel carbonyl concentration. The spectrum shown represents 0.6 ppm of the material. Note the extraordinary absorption strength. The detection limit is thus less than 10 ppb. [Pg.174]

Road materials were gathered from 9 locations on unpaved roads in the vicinity of the sampling site. At each location, dust from the roadbed was scraped into a polyethylene sample bag from 5 or more spots over a 10 m area. These materials were also air dried and sieved Identically to the soil materials, but not crushed. Visual inspections of the road surface suggested that samples from 8 of the 9 sites were primarily crushed limestone rock. The remaining site consisted primarily of washed gravel derived from glacial deposits. An inventory of unpaved road surface materials within 5 km of the sampling site indicated that approximately 80% consisted of crushed limestone. [Pg.306]

Collection. Procedures commonly used to collect vapor-phase organic compounds include whole-air, cryogenic, adsorption, absorption, and de-rivatization methods. Whole-air sampling involves the capture of an air parcel in a container. Stainless steel canisters or plastic bags constructed from an inert material, such as Teflon or Tedlar, are most commonly used. Each of... [Pg.286]

Concerns for the VOC loss from water samples during transportation by air have been raised on occasion. Laboratory studies, however, have demonstrated that there is no discernable difference between VOC data obtained from analysis of water samples shipped by land and by air (Craven, 1998). The notion of unsuitability of air transportation for air samples collected in Tedlar bags is also common. However, if Tedlar bags are filled to 2/3 of their capacity, they survive air travel without leaking or bursting. [Pg.101]


See other pages where Air sample bags is mentioned: [Pg.449]    [Pg.718]    [Pg.72]    [Pg.13]    [Pg.449]    [Pg.718]    [Pg.72]    [Pg.13]    [Pg.186]    [Pg.314]    [Pg.246]    [Pg.267]    [Pg.277]    [Pg.314]    [Pg.911]    [Pg.912]    [Pg.912]    [Pg.916]    [Pg.917]    [Pg.921]    [Pg.931]    [Pg.993]    [Pg.329]    [Pg.188]    [Pg.209]    [Pg.50]    [Pg.71]    [Pg.148]    [Pg.148]    [Pg.180]    [Pg.129]    [Pg.376]    [Pg.305]    [Pg.167]    [Pg.101]    [Pg.113]    [Pg.264]    [Pg.82]   
See also in sourсe #XX -- [ Pg.717 ]




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