Temperature Control Test Procedure

The purpose is to demonstrate the capability of the TTNAC system to control temperature. 

It is the responsibility of validation team members to follow the procedures. The quality assurance (QA) manager is responsible for SOP compliance. 

Note Select test apparatus from 1.1 to 1.3 for data collection. 

Place the Dickson recorder in particular room after fixing new chart on it, for 3 days continuous monitoring. 

After completion of 3 days, remove the chart from recorder. Transfer the recorded data in a working format. 

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Control of an evaporator requires more than proper instrumentation. Operator logs snould reflect changes in basic characteristics, as by use of pseuao heat-transfer coefficients, which can detect obstructions to heat flow, hence to capacity. These are merely the ratio of any convenient measure of heat flow to the temperature drop across each effect. Dilution by wash and seal water should be monitored since it absorbs evaporative capacity. Detailed tests, routine measurements, and operating problems are covered more fuUy in Testing Procedure for Evaporators (loc. cit.) and by Standiford [Chem. Eng. Prog., 58(11), 80 (1962)]. 

BOD test A procedure that measures the rate of oxygen use under controlled conditions of time and temperature. Standard test conditions include dark incubation at 20 C for a specified time (usually 5 days). 

To counter the elevated emissions associated with enrichment, the EPA has adopted supplemental federal test procedures. The new laboratory test procedures contain higher speeds, higher acceleration and deceleration rates, rapid speed changes, and a test that requires the air conditioning to be in operation. These tests increase the probability that vehicles will go into enrichment under laboratory test conditions. Hence, manufacturers have an incentive to reduce the frequency of enrichment occurrence in the real world. Future catalytic converters and emissions control systems will be resistant to the high-temperature conditions associated with engine load, and will be less likely to require enrichment for protection. Thus, enrichment contributions to emissions will continue to decline. 

As reviewed it is important that test specimens or products be properly prepared based on available specifications and/or standards that provide controlled conditioning procedures when conducting weathering as well as all other tests. The following is one example. There are other conditions set forth to provide for testing at higher or lower levels of temperature and humidity. 

Alkaline phosphomonoesterase (EC 3.1.3.1). The existence of a phosphatase in milk was first recognized in 1925. Subsequently characterized as an alkaline phosphatase, it became significant when it was shown that the time-temperature combinations required for the thermal inactivation of alkaline phosphatase were slightly more severe than those required to destroy Mycobacterium tuberculosis, then the target micro-organism for pasteurization. The enzyme is readily assayed, and a test procedure based on alkaline phosphatase inactivation was developed for routine quality control of milk pasteurization. Several major modifications of the test have been developed. The usual substrates are phenyl phosphate, p-nitrophenyl-phosphate or phenolphthalein phosphate which are hydrolysed to inorganic phosphate and phenol, p-nitrophenol or phenolphthalein, respectively ... 

The use of steam at 100°C or above would provide an accelerating effect, although this would probably be considered too severe for most applications. Such a test would, however, be relevant for a product such as hose intended for use with steam and the particular test procedure would be found in the product specification. In designing any tests for exposure to steam it is necessary to control the amount of air (if any) present since oxygen at the temperatures used would have a strong deteriorating action. 

Accurate temperature calibration using the ASTM temperature standards [131, 132] is common practice for DSC and DTA. Calibration of thermobalances is more cumbersome. The key to proper use of TGA is to recognise that the decomposition temperatures measured are procedural and dependent on both sample and instrument related parameters [30]. Considerable experimental control must be exercised at all stages of the technique to ensure adequate reproducibility on a comparative basis. For (intralaboratory) standardisation purposes it is absolutely required to respect and report a number of measurement variables. ICTA recommendations should be followed [133-135] and should accompany the TG record. During the course of experiments the optimum conditions should be standardised and maintained within a given series of samples. Affolter and coworkers [136] have described interlaboratory tests on thermal analysis of polymers. 

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