Small-scale test chamber

Upon completion of the chamber test, the hardwood plywood paneling or particleboard is removed and 12 each 7.00cm x 12.7 cm specimens are randomly cut from each board loaded into the chamber. For the surface monitor (FSEM) and the small scale test chamber(SSTC), one 30.5cm X 30.5cm board is cut from each board loaded in the chamber. These samples are immediately tested by the Equilibrium Jar for particleboard or the Two Hour Desiccator or FSEM or SSTC for all wood product types. The values obtained from each test are averaged and are then compared to the chamber concentration observed for that loading and air change rate. 

Our Small Scale Test Chamber (SSTC) is constructed of 2 cm thick plywood. The interior of the small chamber is lined with the same aluminum used in the large scale test chamber. The exterior surface is painted with an epoxy paint. Dimensions of our SSTC are similar to the SSTC developed at Oak Ridge National Laboratories. The interior dimensions are 63 cm x 63cm x 61cm with an internal volume of 241 liters. The internal equipment occupies about 2 liters thus giving an adjusted volume of 239 liters. 

Based on our experience, it appears that a quality control method which correlates to the chamber for a particular product type does not always work for all products. The only universal test method for all products is the large scale test chamber. A quick and reliable formaldehyde quality control test method is becoming more important as formaldehyde levels in the chamber fall below 0.15. A universal small scale test method (Q.C.) does not seem to exist at this time. However, the Small Scale Test Chamber may be the closest to fulfilling that purpose. 

Black, M.S. "Correlation Of Wood Product Formaldehyde Emission Rates As Determined Using A Large Scale Test Chamber, Small Scale Test Chamber, and Formaldehyde Surface Emission Monitor" Georgia Institute of Technology, April 18, 1985. 

ASTM (1997) D5116-97. Standard Guide for Small-Scale Environmental Chamber Determinations of Organic Emissions from Indoor Materials/Products, American Society for Testing and Materials, Philadelphia, PA,USA. 

California Dept of Health Services The Collaborative for High Performance Schools (CHPS) Section 01350 Standard practice for the testing of volatile organic emissions from various sources using small-scale environmental chambers ... 

California Department of Health Services (2004) Standard Practice for the Testing of Volatile Organic Emissions from Various Sources Using Small-Scale Environmental Chambers, California Health and Human Services Agency, California, USA. 

Despite the understanding that smoke obscuration ought to be measured in a large scale, or by a method which can predict large-scale smoke release, the most common small-scale test method for measuring smoke from burning products is the traditional smoke chamber in the vertical mode (ASTM E 662)39 (Figure 21.14). The test results are expressed in terms of a quantity called specific optical density, which is defined in the test standard. This test has now been shown to have some serious deficiencies. The most important problem is misrepresentation of the smoke... 

Salthammer T (ed) (1999) Organic indoor air pollutants. Wiley-VCH, Weinheim American Society for Testing and Materials (1997) Standard guide for small-scale environmental chamber determinations of organic emissions from indoor materials/ products. ASTM D 5116-97. ASTM International, West Conhohocken,PA... 

Generally the chamber design depends on the atomizer used and on the air-fluid contact system selected. The selection of atomizer and air-fluid layout is determined by the required characteristics of the dry product and production rate. The product specifications are almost always determined from small-scale tests in an experimental spray dryer. Sometimes they are available from the literature. If heat-sensitive material is involved, attention must be paid to the temperature... 

Evaluation of VOC and SVOC emission potential of individual products and materials under indoor-related conditions and over defined timescales requires the use of climate-controlled emission testing systems, so-called emission test chambers and cells, the size of which can vary between a few cm3 and several m3, depending on the application. In Figure 5.1 the dots ( ) represent volumes of test devices reported in the literature. From this size distribution they can be classified as large scale chambers, small scale chambers, micro scale chambers and cells. The selection of the systems, the sampling preparation and the test performance all depend on the task to be performed. According to ISO, chambers and cells are defined as follows ... 

The cone calorimeter,71 which is a dynamic flow-through fire test, can also be used to assess smoke obscuration. The rankings tend to be quite different from those found with the static smoke chamber and are much more realistic. Several empirical parameters have been proposed to make this compensation for incomplete sample consumption, including one called the smoke factor (SmkFct), determined in small-scale RHR calorimeters.188 It combines the two aspects mentioned earlier the light obscuration (as the total smoke released) and the peak RHR. 

Cacodyl oxide reaction If a dry acetate, preferably that of sodium or potassium, is heated in an ignition tube or test-tube with a small quantity of arsenic(III) oxide, an extremely nauseating odour of cacodyl oxide is produced. All cacodyl compounds are extremely POISONOUS the experiment must therefore be performed on a very small scale, and preferably in the fume chamber. Mix not more than 0-2 g sodium acetate with 0-2 g arsenic(III) oxide in an ignition tube and warm observe the extremely unpleasant odour that is produced. 

This method is suitable for stored-product pests. The evaluation of toxic vapor is a somewhat similar operation. The insecticide is introduced into a sealed container along with the insects and mortality is recorded at different intervals. Various fumigation techniques were described by Busvine (1971), including (1) small-scale techniques for measuring the susceptibility of exposed insects and (2) semipractical tests using large fumigation chambers. 

ABSTRACT Calcium-enriched bio-oil (CEB) can be used for flue gas desulfurisation in coal and waste combustion chambers. It is produced by mixing biomass derived fast pyrolysis oil with calcium oxide. The aim of the proposed project is to develop a technology i) to produce calcium-enriched bio-oil with a calcium content of 13 wt,%, and ii) to test the CEB in a combustion chamber by co-firing it with a sufur-containing fuel. In this paper the production method of CEB will be elucidated, and small-scale experiments related to CEB spraying will be presented. Finally, co-combustion experiments of a sulfur-containing fuel with CEB in a small flame tunnel (20 kW, ) will be reported. 

In-plant quality control and routine acceptance testing by property verification organizations such as the Hardwood Plywood Manufacturers Association and the National Particleboard Association require a method more efficient than the chamber for routinely monitoring trends in emission characteristics of products. The relationship between chamber and the small scale desiccator test observations is illustrated by a series of 76 tests accomplished during the past year on hardwood plywood wall panel products at a chamber loading rate of 0.29 sq ft per cu ft ... 

The incidence of perceptible formaldehyde in homes, offices and schools has caused widespread uncertainty about the safety of living with formaldehyde. This uncertainty was enhanced by the large scale installation of urea formaldehyde foam insulation (UFFI) because a substantial part of this material was made from small scale resin batches prepared under questionable quality control conditions, and was installed by unskilled operators (10). The only reliable way to avoid such uncertainty is to know the emission rate of products and develop a design standard that allows prediction of indoor air levels. The first and most important step in this direction was achieved with the development and implementation of material emission standards. As indicated above, Japan led the field in 1974 with the introduction of the 24-hr desiccator test (6), FESYP followed with the formulation of the perforator test, the gas analysis method, and later with the introduction of air chambers (5). In the U.S. the FTM-1 (32) production test and the FTM-2 air chamber test (33) have made possible the implementation of a HUD standard for mobile homes (8) that is already implemented in some 90% of the UF wood production (35), regardless of product use. 

Two very promising alternatives for treating dioxin - contaminated soil are the Shirco process and the thermal desorption method. The Shirco process places contaminated soil on a moving grate. The soil is heated by infrared heaters or by burners, and vapors are destroyed in a secondary combustion chamber. This process has been demonstrated on a small scale at the Times Beach test facility and will be tested further under various private and governmental sponsorships. 

Small-scale chambers Relatively low cost of construction and operation Need for replicate tests (sample inhomogenity)... 

In Fig. 2.1-1, the general arrangement of an environmental test chamber is shown. Basically, two types of environmental test chambers can be distinguished small scale chambers with volumes ranging from a few litres to a few cubic metres, and room-size large scale chambers of the walk-in type. Both types of chambers have advantages as well as disadvantages (see Table 2.1-1) (EC, 1989). 

Preliminary small scale combustion tests carried out with the pyrolysis oil as produced (20% water content) showed that it burns readily in a furnace with a conventional pressure atomizing burner, providing the combustion box is preheated. If an air atomizing nozzle is used with a pilot flame, no pre-heating of the combustion chamber is necessary. Larger scale tests for extended periods have not yet been done, but preliminary work shows that the pyrolysis oil has potential as a substitute fuel oil. 

The small scale closed tester is a metal cup with a thermometer fitted below the bottom of the internal chamber with ahinge mounted cover having filling orifice. The sample is introduced to the cup and the cup is maintained at a constant temperature by means of temperature controller. After a specific time, a test flame is applied for 2.5 s and an observation is made whether or not flash has occurred. If flash did not occiu the cup is cleaned, a new sample is introduced and the temperature is increased by 5 C. The measurements are repeated until the flash point is determined with accuracy of 1 C. 

Small-scale flammability is examined by the spirit burner flame test, 24 test pieces of 150 X 25 mm are cut from a belt, half of them parallel, the other half perpendicular to the length of the belt. 3 pieces of each are tested with covers intact while the other 18 are stripped of the covers for a length of at least 50 mm at the tested end. The test piece is inserted into a holder so that it projects at least 50 mm beyond the edge of the holder. In the test chamber of 660 x 610 x 1070 mm, black inside, the specimen is ignited by a spirit burner for 30 s as shown in Figure 3.138. The time of flaming or glowing after the withdrawal of the burner is measured. 

Additional safety considerations apply to the use of microwave technology. First, the equipment should be operated in strict accordance with instructions to ensure that no detectable amounts of microwave radiation will escape. Leak tests should be conducted on a regular basis by a trained technician. Vessels or other objects made of metal should never be placed in the oven chamber. Microwave equipment must also never be operated empty (i.e.. in the absence of a sample solution, water, acid, etc.), since the magnetron might be destroyed by reflected radiation. The behavior of unknown samples should be tested on a small scale (see above). 

Obscuration is typically measured in the NBS smoke chamber (ASTM E 662). This is a small scale laboratory test of a sample exposed to a radiant energy source, either with or without an adjacent pilot flame to ignite the gases from the material. 

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