Testing conditions humidity

The electrical properties will also depend on the above factors as well as on the test conditions, in particular temperature, test frequency and humidity. Table 26.12 quotes ranges for figures quoted in the literature for various electrical properties. 

European Norm EN 321, Wood fibre panels — cycle tests under humid conditions, 1994. European Norm EN 622-2, Wood fibre panels — Specification requirements for hitrd-board, 1998. 

The catalogue-rated cooling capacity of a room air-conditioner, if not qualified, will be based on ASHRAE Standard 16-1983. This specifies test conditions of air onto the evaporator at 80°F dry bulb, 50% relative humidity (26.7°C, 49.1% saturation), and air onto the condenser at 95°F dry bulb, 75°F wet bulb (35°C and 23.9°C). The original basis for this specification was the ambient condition prevailing in the mass-market area of the USA. 

The tensile data can be applied to the design of short-term (such as 1 or 2 hour duration) or intermittent loads in a product provided the use temperature, the humidity, and the speed of the load are within 10% of the test conditions outlined under the procedure. The intermittent specification merely indicates that there be sufficient time for strain recovery after the load has been removed. 

Geochemical simulations (not shown) of water quality suggest that Ni is soluble in the test conditions, eliminating secondary mineral precipitation as an explanation for the absence of Ni in leachates. These observations could be explained by the metal retention potential of the Lac Tio waste rock being still active in the humidity cell tests. Consequently, the Ni produced in the humidity cell tests will continue to be retained by the fresh waste rock until saturation of the retention sites. 

Weatherfastness tests on coatings have shown that prolonging the dry and wet periods, i.e., extending the usual 17 minute dry cycle to a full 102 minutes and the wet period to 18 minutes, affords results which correlate much better with the Florida outdoor exposure tests. The humidity that penetrates a layer is known to interact with the various components in the coating, adversely affecting the mechanical properties of the material. The above mentioned cycle apparently corresponds much better with the climatic conditions in areas like Florida. If recirculated water is used in accelerated exposure equipment, suspended particles may adhere to the surface of the coating, producing a thin film. This obviously has a detrimental effect on the test results. 

As described in Section V, A. 2, satisfactory long-term stability of sealed cells has been already achieved under relatively mild test conditions (low temperatures and no UV exposure). For outdoor applications, additional stability tests under more rigorous conditions will be required (e.g., high temperature such as 80°C, high humidity in the atmosphere, and UV exposure). 

It is fairly obvious that other factors such as lubricants, wear debris, ageing of the surfaces and humidity can also affect friction and, once again, test conditions must be chosen that resemble those found in service. 

The result is always expressed as a transmission rate, not a permeability, and is, hence, dependent on test piece thickness. Generally, transmission rate is not a linear function of temperature or relative humidity and, preferably, test conditions are chosen to be as close as possible to those found in service. 

In Finland, investigations into stepwise carbonation processes initially involved the use of Finnish serpentine and (calcined) magnesium hydroxide powder ( 20gm, 99% pure) in a PTGA with humid C02, at 0.1 to 3.5 MPa pressure. The materials were first heated to 1273 K, and then cooled in (mainly) C02/N2 mixtures. Tests conducted at elevated pressures did not produce the expected increase in MgO carbonation rate, as the final carbonation conversions fell from 5.6% at 0.1 MPa to 2.9% at 3.5 MPa in 99%/l% C02/H20. Hence, the decision was taken to proceed with Mg(OH)2 under test conditions where MgO formation was thermodynamically unfavorable [85, 96]. 

SASTM Test Methods D-1037-72, Pt. l6, with exceptions of certain sample sizes and the nonstandard 1-hour boil Basis, dimension at conditioned humidity Basis, weight at conditioned humidity 3Basis, initial IB... 

A gravimetric method is often used for the measurement of water vapor permeability. The water vapor transmission rate (WVTR) according to this method is the amount of water vapor in g that permeates in 24 hours under standard test conditions (temperature, air relative humidity, water vapor sorbant) through aim2 sample surface area. The method measure a flux and not a permeability coefficient. 

Test conditions of temperature 20 5 °C, humidity 50 10%, atmospheric pressure and no wind are suitable 1. ... 

The temperature/humidity conditions used may be more severe than the typical accelerated stability testing conditions in order to generate potential degradation products in a reasonable time. The typical forced degradation conditions include thermolytic, hydrolytic, oxidative, photolytic (in excess of ICH conditions), high pH (alkaline conditions), and low pH (acidic conditions). Outlined in Table 9-25 and Table 9-26 are some solid-state and solution forced degradation studies, respectively, that could be conducted. In the following... 

Laboratory tests confirmed that in the absence of effective corrosion inhibitors molybdenum disulphide could cause corrosion in humid environments. Kay ° showed in tests with different steels that corrosion was accelerated in the presence of loose molybdenum disulphide powder, especially ball-milled or micronated powder. Her test conditions were realistic, namely 20 C and 90% relative humidity for six days, but the use of loose powder was not representative of practical use, and it subsequently became clear that burnished films were less active in promoting corrosion. Calhoun et al also showed that molybdenum disulphide in a bonded film actively promoted corrosion, although their test conditions were severe, consisting of salt fog and salt spray tests. They found that corrosion was more severe when graphite was present, but that molybdenum disulphide also clearly caused corrosion. 

A raw gas concentration of between 10-2000 mgW was selected so as the tests in the laboratory adsorption unit and pilot plant could be conducted in an acceptable time span. Flow velocity during adsorption was 0.1-0.5 m/s while relative humidity was set at between 20% and 70%. Each of the measurements was performed at room temperature (20°C to 25°C). The number of ACC layers used in the tests varied between 2 and 10 layers, depending on the parameter to be measured. Table 1 contains specific data on the plant as well as the test conditions. 

There are generally two types of stability studies conducted 1) regular and 2) accelerated. In the case of accelerated stability study, the product is stored under elevated temperature and relative humidity (RH) conditions to force or expedite its degradation pathway and assess the changes. The stability testing conditions depend on the anticipated market environment. An example of a recommended protocol is provided in Table 1. 

Stress testing is likely to be carried out on a single batch of material and to include the effect of temperatures in 10 °C increments above the accelerated temperature test condition (e.g., 50 °C, 60 °C, etc.) humidity where appropriate (e.g. 75% RH or greater) oxidation and photolysis on the drug substance plus its susceptibility to hydrolysis across a wide range of pH values when in solution or suspension. 

According to the thermal/humidity stress testing conditions selected, samples are placed into appropriate ovens. If humidity ovens capable of 70°C/30% RH and 70°C/75% RH are not available, saturated salt solutions contained in desiccators can be used to control humidity accurately. These conditions are particularly useful for high-potency drug substance compounds for which samples must be contained. A saturated NaCl solution is used to obtain conditions of 75% RH at 70 °C and a saturated MgCl2 solution is used to obtain conditions of 30% RH at 70 °C. 

These test chambers can be incorporated to the enzymatic methods for formaldehyde determination. Formaldehyde emissions of a product, or mix of products, to the ambient air can be collected in distilled water or 1% sodium bisulfite as the absorbing solution. After collection, formaldehyde samples are analyzed as described above. In the mobile home simulator test method (2J, double or triple impingers, which are placed in series, should be used in order to collect all of the formaldehyde vapor. The test conditions should simulate the actual environment. Several factors such as temperature and relative humidity of the system including the specimens and background of formaldehyde in the test chamber, affect the precision and accuracy of the results. It has been shown that a 7 C change in temperature doubles the emission level (L). The temperature of the test chamber should be... 

Emission. As the emission varies considerably with temperature and relative humidity of the air (2) it is necessary that the test is performed at constant climate. Our test conditions were in agreement with the tentative mehod of CEN (J,). 

It should be noted that efficiency of additives action depends on the testing conditions (intensity and spectral composition of the irradiation source, humidity, concentration of additives and so on). This is connected with the fact that stabilizers may at the same time act according to several mechanisms, but only one of them is realized depending on testing conditions. 

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