Standard and reference conditions

Record all operating details and conditions, including yields, product or compound names, lot numbers of standards and reference materials, suppliers, and anyexpiration dates. 

For biopharmaceuticals, storage conditions are critical to maintain activity. Normal ICH stability studies are conducted with reference to global climatic zones under standard and accelerated conditions over time periods of up to 5 years. For biopharmaceuticals, this may not be appropriate, and specific coohng conditions (2-8°C, <-20°C) may have to be provided to keep the product intact (see Section 1.4.6). Furthermore, the container and the closure system used for final market presentation (e.g., vial with mbber) must be investigated for interaction potential. Last -but not least - the stability of the reconstituted solution in the case of lyophilisate, or diluted solutions in the case of infusion therapy, must be characterized. 

A broad range of technical requirements is important in a laboratory quality system. These include aspects such as the selection of appropriately qualified and experienced personnel sampling, sample handling and preparation laboratory accommodation and environmental conditions equipment and reagents calibration reference standards and reference materials traceability (of standards and of samples) the selection or development, validation, and control of methods estimation of the uncertainty of measurements reporting of results and quality control and proficiency testing. 

The thermodynamics of electrochemical reactions can be understood by considering the standard electrode potential, the potential of a reaction under standard conditions of temperature and pressure where all reactants and products are at unit activity. Table 1 Hsts a variety of standard electrode potentials. The standard potential is expressed relative to the standard hydrogen reference electrode potential in units of volts. A given reaction tends to proceed in the anodic direction, ie, toward the oxidation reaction, if the potential of the reaction is positive with respect to the standard potential. Conversely, a movement of the potential in the negative direction away from the standard potential encourages a cathodic or reduction reaction. 

Condensed from Fundamentals, American Society of Heating, Refrigerating and Air-Conditioning Engineers, 1967 and 1972. Reproduced by permission. Tbe validity of many standard reference tables bas been critically reviewed by Jancso, Pupezin, and van Hook, J. Fhys. Chem., 74 (1970) 2984. Tbis source is recommended for further study. Tbe notation 4.949.-8, 3.607.-I-9, etc., means 4.949 x 10 , 3.607 x 10, etc. 

Are lockout/tagout devices in good condition, clearly identified, standardized, and durable [OSHA Reference, 147(c)(5)(ii)]... 

The standard requires controlled conditions to include compliance with reference standards/codes, quality plans, and/or documented procedures. 

The ratio f/f° is called activity, a. Note This is not the activity coefficient. The activity is an indication of how active a substance is relative to its standard state (not necessarily zero pressure), f°. The standard state is the reference condition, which may be anything however, most references are to constant temperature, with composition and pressure varying as required. Fugacity becomes a corrected pressure, representing a specific component s deviation from ideal. The fugacity coefficient is ... 

Standard Ton Conditions. These are taken by industry to represent the refrigeration tonnage of a system when operating with an 86°F condenser temperature and a 5°F evaporator temperature. This is a comparative reference condition and does not need interpolation for effective evaluation of other tonnage requirements and conditions. 

A very substantial literature may now be found for electropolishing solution formulation and Table 11.5 gives some of the well-established compositions and operating conditions. Further solutions may be found in the standard reference books and for specialist applications and metals... 

Two conditions that are often important in chemical experiments are temperature and pressure. Consequently, chemists usually control and measure these conditions during experiments. In addition, it is useful to refer many experimental results to a standard and generally accepted set of temperature and pressure conditions. This facilitates comparison of results of different types and from different laboratories. 

To obtain comparative values of the strengths of oxidising agents, it is necessary, as in the case of the electrode potentials of the metals, to measure under standard experimental conditions the potential difference between the platinum and the solution relative to a standard of reference. The primary standard is the standard or normal hydrogen electrode (Section 2.28) and its potential is taken as zero. The standard experimental conditions for the redox... 

This chapter has shown, however, that errors can be investigated and evaluated with more assurance in x-ray emission spectrography than in the general run of analytical methods. The standard counting error (10.3) can serve as a satisfactory criterion of operating conditions and as a standard of reference to which the other errors are conveniently -compared. But it is manifestly unwise to assume without proof, as has often been done, that the standard counting error gives the precision of the analytical result. 

The ASME Consensus was first published in 1979 and has been a standard reference ever since for boiler water treatment practice in the United States and its sphere of influence. The ASME Consensus 1994 update reflected the need to cover technical advances in boiler design and water conditioning, and also new and different types of steam generator, steam purity issues, and similar matters. 

Activity can be thought of as the quantity that corrects the chemical potential at some pressure and/or composition condition" to a standard or reference state. The concept of a standard state is an important one in thermodynamics. The choice of the pressure and composition conditions for the standard state are completely arbitrary, and unusual choices are sometimes made. The common choices are those of convenience. In the next section, we will describe and summarize the usual choices of standard states. But, first, we want to describe the effect of pressure and temperature on a,. 

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