Outdoor testing

Because of safety concerns, all combustible and/or toxic gases must be used in outdoor test loops or in a special indoor test building with the required safety monitoring equipment. The gas cost factor makes the problem even more difficult. The problem of known gas properties adds another complication. Despite all the negative aspects just mentioned, most performance tests are closed-loop tested. 

The influence of moisture is fundamental, as it is with other forms of corrosion. Long-term contact tests with ponderosa pine, some treated with zinc chloride, in atmospheres at 30, 65 and 95% r.h. showed that at 30 and 65% r.h. plain wire nails were not very severely corroded even in zinc chloride-impregnated wood. At 95% r.h. plain wire nails were severely corroded, though galvanised nails were attacked only by impregnated wood. Brass and aluminium were also attacked to some extent at 95% r.h. Some concurrent outdoor tests at Madison, Wisconsin, showed that the outdoor climate there was somewhat more severe than a 65% r.h. laboratory test. 

Outdoor testing is the most accurate method of obtaining a true picture of other resistance. The only drawback of this test is the time required for several years exposure that are usually located in different climatic zones around the world. A large number of specimens are usually required to allow periodic removal and to run representative laboratory tests after exposure. 

Pine sapwood acetylated to 22 % WPG exposed for 1 year at an outdoor test site in Indonesia showed a weight loss of only 2 % due to termite attack, whereas unmodified controls lost 93 % in weight in the same period (Westin etal, 2004b). 

To keep things simple, we deliberately left antidotes out of the design. We also thought it best to carry out the experiment indoors, in a secure environment. Less than a month earlier, we had tried an outdoor test with some worrisome results. These occurred when Colonel Frank Bauer, Doug Lindsey s replacement as Chief of the Medical Laboratories, approved our request to construct an obstacle course to test volunteer performance in a physically challenging outdoor environment. 

Given this erratic behavior, we decided outdoor testing carried a significant risk of injury, even with close supervision. As always, we believed that safety concerns should take precedence over outdoor realism. 

Comparison of Laboratory Tests and Outdoor Tests of Paint Coatings for Atmospheric Exposure... 

Table IV shows that acetylation greatly reduced weight loss and errosion rate due to loss of surface fiber from aspen flakeboards. The rate of errosion for boards made from acetylated flakes is half that of control boards. In outdoor tests, flakeboards made from acetylated pine flakes were still light yellow in color when control boards had turned dark orange to light gray.

Figure I. Results of an 8-month outdoors test of PEC containing a 0.8-cm2 thin film, painted CdSe photoelectrode (not photoetched), CoS counterelectrode, and 7M KOH, 2M S, 7M S, ImM Se solution. (OCV) open-circuit voltage (SCC) short-circuit current (EFF) solar conversion efficiency ( AMI.5). Between measurements the cell operated on maximum power (68 fi load). No appreciable change in fill-factor occurred during the test.

However, the studies EPA requires are not necessarily conducted within the confines of the traditional indoor scientific laboratory... EPA considers any site where testing is undertaken, for data required by the Agency, to be a testing facility. The conditions required by the protocol are not conducive to artifical manipulation in the field, or other outdoor testing facilities. Therefore, ensuring the suitability of the location of these types of testing facilities is both a valid and necessary part of EPA s GLP Standards. 

Douglas-fir, birch, southern pine, and sweetgum blocks were treated with 1% aqueous ammonia or sodium hydroxide for various times, temperatures, and pressures (9). These samples were submitted to soil-block tests with two brown-rot fungi Poria monticola (Madison 698) and Lentinus lepideus (Madison 534) and two white-rot fungi Polyporus versicolor (Coriolus versicolor) (Madison 697) and P. anceps (F 784-5) as well as outside exposure tests (10). In the soil-block tests, the treated wood was resistant to the two brown rotters, but was not resistant to the two white rotters. In the outdoor stake tests, the average lifetime was 3.5 years while untreated controls had an average lifetime of 3.6 years. The outdoor tests show that there is no increase in rot resistance by this treatment. 

Advanced Genetic Science Field-tested Frostban —a GE bacterium that inhibits frost formation on crops the first outdoor tests of a GE organism... 

Direction and force of air currents (wind)—Tests involving similar firings with the same gun and ammunition batch, one series conducted indoors and the other outdoors, produced substantially less FDR on the firer in the case of the outdoor tests. This was thought to be due to the... 

A second generation, and far more effective photo-degrading additive system was later developed and extensive indoor and outdoor testing was done. With such an effective system it was obvious that its use could go much further than just agricultural mulch films. 

The methods and procedure are described under Testing Method and Test Equipment. Ten film specimens were arbitrarily chosen for comparison of indoor and outdoor testing. Results are shown in Table 6. 

Outdoor Tests. One standard protocol for atmospheric corrosion testing is to mount small rectangular plates (1.6 x 2.4 cm) on a test rack at about 30 from horizontal, about 3 feet off the ground, usually facing south (Figure 4). The test plates are held off the rack by porcelain insulators, and although strictly speaking a new boundary layer should form on each plate, there may be some positional differences in corrosion rate due to turbulence created by the plates first encountered by the wind flow. 

Reference (3) reanalyzed data from a number of such outdoor test sites and derived an SO2 deposition velocity of 1.55 - 1.75 cm./sec. for zinc, operable only during times of surface wetness. In that report, reference was made to SO2 deposition velocities over water surfaces (1.6 cm/sec), which are likely to be low turbulence situations. It was also noted that the deposition velocity to water is dependent upon atmospheric stability. SO2 deposition velocities for copper and aluminum were less straightforward (3), but appeared to be somewhat lower, perhaps reflecting less chemically active surfaces. The zinc result is reasonably consistent with the theoretical values developed above from boundary layer theory and tests, since it lies between these values (1.2 - 3.7 cm/sec). Incorporating actual test site wind speeds could obviously help reduce the scatter in these determinations. 

In both the outdoor tests reanalyzed by Lipfert et al. (3) and the chamber tests of Edney et al., (13) it was deduced that zinc was removed stoichiometrically by the deposited S02> implying no chemical surface resistance. However, in the case of outdoor tests, this conclusion is conditional on the deposition velocity. 

We were unable to find in the literature any test data of blunt building-like shapes at sufficiently high Reynolds numbers to simulate real buildings. We did find tests of small square prisms in a wind tunnel (low turbulence), (17) and outdoor tests with... 

Chamber Tests Outdoor Test Racks Large Buildings ... 

In an attempt to improve the foliar persistence of Bt insecticidal activity, Mycogen Corporation has developed the MCap delivery system, based on an rDNA microorganism that expresses a Bt toxin, but has been killed via heat and chemical treatment prior to field release Q). Because the organisms are dead, this product has the additional advantage of relative freedom from the environmental and safety concerns associated with outdoor testing of living rDNA organisms. 

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