Test methods initiation

When a voltage is applied to a dielectric (insulator), a current passes that decays with time owing to various polarization mechanisms [ 133]. Conductivity is always time-dependent. This general time dependency affects conductivity measurement for nonconductive liquids, where the peak initial current is used to calculate conductivity. Test methods are given in 3-5.5 and... 

The latest CARB/EPA procedures require diurnal emissions to be measured during a real time, three day test that exposes the complete vehicle to daily temperature fluctuations. This test method has been employed to more accurately reflect the real world diurnal emissions that occur. Rutming loss emission measurements were also initiated in the latest test procedures. Evaporative emissions are measured... 

The strains needed to initiate cracks in both the annealed and the sensitised materials were obtained using tapered slow-strain-rate specimens and the data are given in Fig. 8.36. As can be seen, there is little temperature dependence of the strain needed to initiate cracks in sensitised material whereas the annealed material was most susceptible to cracking at about 250°C. These results indicate the complicated response of Type 316 stainless steel to applied potential and demonstrate that, even though environmentally-assisted cracking may be generated by severe test methods, in this case the slow-strain-rate test, the results obtained must be used with care. For instance, the cracking of the annealed material at low potentials... 

Under micro-discontinuous chromium coatings, copper undercoats improve corrosion resistance. On non-conductors, especially on plastic substrates, copper is often applied before nickel-chromium plating over the initial electroless copper or nickel deposit in order to improve ductility and adhesion, e.g. as tested by the standard thermal-cycling test methods ... 

Temperature effects may also be used in test methods and notably for assessing the effects of inhibitors in acid solutions. The technique is based on that first proposed by Mylius which records the temperature-time behaviour associated with the exothermic reaction resulting from the initial contact of a metal with a corrosive acid solution. The effectiveness of inhibitors may then be determined from their effects on the temperaturetime behaviour. ... 

Test method Experimental conditions Sample mass Initial exotherm detected, K Adiabatic temperature increase, K Heat of reaction, J/g... 

A description is given of the initiatives carried out within the European Community for the harmonization of fire testing. The technical and economic reasons are explained for such initiatives, which are taken in order to remove barriers to trade from the European internal market. Of the various fire aspects, only fire reaction testing is taken into consideration here, because it appears as a major technical obstacle to the free circulation of construction materials. All possible approaches are considered for the attainment of such a harmonization and one, the so called interim solution, is fully described. The proposed interim solution, is based on the adoption of three fundamental test methods, i.e. the British "Surface Spread of Flame", the French "Epiradiateur" and the German "Brandschacht", and on the use of a rather complicated "transposition document", which should allow to derive most of the national classifications from the three test package. 

Cronin, J. L., and P. F. Nolan, "The Comparative Sensitivity of Test Methods for Determining Initial Exotherm Temperatures in Thermal Decompositions of Single Substances," J. Haz. Mat., 14 (1987). 

Cachia, G. P. und Withebread, E. G. The Initiation of Explosives by Shock, Proc. Roy. Soc. A 246, 268-273 (1958). Card-Gap Test for Shock Sensitivity of Liquid Monopropellant, Test Nr. 1, Recommended by the JANAF Panel on Liquid Monopropellant Test Methods, March 1960 Amster, A. B., Noonan, E. C. und Bryan, G. J. Solid Propellant Detonability, ARS-Journal 30, 960-964 (1960)... 

After construction of the piping system and after completion of the applicable examinations and repairs, but prior to the initial operation, each piping system shall be tested to ensure tightness. The test method and extent of testing shall be as required by the applicable Part IP or PL. 

The front end of this tier approach is a screen, the functional observation battery (FOB) Gad (1982) or Irwin (1968) screen. This is the tool of choice for initial (and for most of the compounds covered by this volume, the only screen tests for) identification of potentially neurotoxic chemicals. The use of such screens, other behavioural test methods, or what are generally called clinical observations does, however, warrant one major caution or consideration. That is that short-term (within 24 hr of dosing or exposure) observations are insufficient on their own to differentiate between pharmacologic (reversible in the short term) and toxicological (irreversible) effects. 

Safety of Reactive Chemicals and Pyrotechnics (Yoshida et al. 1995). Addresses both the hazardous properties of reactive chemicals and appropriate handling methods. Describes several test methods and the evaluation of fire and explosion hazards of reactive substances, including the impact of initiating events such as earthquakes. 

The minimum temperature for a specified test method, test apparatus (including material of construction and test volume) and initial pressure required to initiate self-sustained decomposition of a solid, liquid or gaseous substance without any other apparent source of ignition and without air or other oxidants present. 

Aquifer test analyses can be conducted by one or several methods depending upon whether the solution is applied to a specific aquifer type and with certain assumptions being made on the hydrogeologic nature of the aquifer and nature of the test. The initial analytical methods employed assume that the aquifer is... 

For petroleum and petroleum product releases in a nonsensitive area (if there is such an area), the analytical methods preferred to determine the concentration of total petroleum hydrocarbons in environmental media is the standard EPA test method (EPA 418.1). For initial delineation of the area, test field kits may be used in nonsensitive areas, provided that the results are comparable to laboratory data. Final confirmatory sampling and analyses should be carried out using laboratory analyses. 

Several methods for performing the test have been described, the guideline describes the diffusion and suspension test. Bacteria should be exposed to the test substance both in the presence and absence of an appropriate metabolic activation system. The response is expressed in the preferential inhibition of growth or the preferential killing of the DNA repair deficient strain. Escherichia coli polA (W3110/p3478) or Bacillus subtilis rec (H17/M45) pairs are recommended. The test should initially be performed over a broad range of concentrations. 

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