Critical product parameters

Ensure that vendors in-process controls include the use of statistical process control critical product parameters that are significant and may affect the final product quality... 

Critical product parameters Collected data and its analysis... 

Set Objectives > Document Critical End Product Parameters > Confirm Measurement System Baseline End-Product Parameters Process Potential Diagnostics... 

Confirm Measurement System > Baseline In-Process Product Parameters (Control, Capability) > Identify/Prioritize Process Steps > Identify Critical Process Parameters... 

A third approach has been suggested by Jaroudi (Jl), who points out that one necessary condition to prevent reignition of the propellant is to ensure that the gas temperature resulting from thermal equilibrium between the injected fluid and the combustion products is below the propellant autoignition temperature. This approach leads to the conclusion that the ratio of coolant mass flow to propellant mass flow is the critical correlating parameter. 

This part concerns the actual quality control system by which the critical product and process parameters that impact final quality attributes are monitored and corrected in the production process. CQP monitoring systems can be based on the principle of a control circle as explained in Section 7.1.3. The following principles must be followed ... 

Identification and evaluation of critical product and process parameters affecting Q attribute Allocating critical process steps (where)... 

The value of critical concentration depends strongly on the pectin being used. Figure 2 gives the viscosity curves of two different pectins at the same concentration of 2.5 % w/w. The different production parameters, that have been used for these pectins, have strongly influenced their flow behaviour. The enzymatic reduction of the molecular weight down to... 

Currently the main application of interest for parametric release is to replace the sterility test as a control method in appropriate cases (given the limited value of that test to predict sterility assurance due to statistical considerations, although it is also pointed out that a sterility test provides a final opportunity to identify a major failure, although other means should provide a more reliable way of detecting such failures). The concept is applicable to well-founded methods of sterilization where the product stability is known and development data have identified the critical process parameters. The measured parameters should be such as to ensure that correct processing of the batch provides sufficient assurance that the sterility assurance level intended has been achieved. 

Finally, a group from General Motors has explored the mechanistic importance of the N20 + CO reaction as an intermediate step during the reduction of NO by CO on noble metal exhaust catalysts [87,88]. Quasi-linearization of the non-linear NO + CO reaction system by identifying a critical kinetic parameter revealed that, indeed, the rate of the N20 + CO conversion as an intermediate step in the overall NO + CO conversion can be two to three orders of magnitude faster than the isolated N20 + CO reaction. This suggests that the observed suppression of N20 production at higher temperatures may be due to its fast reaction with adsorbed CO once produced, and that, contrary to the accepted wisdom, the formation of N20 and its subsequent reaction with CO can make a major contribution to the kinetics of the reduction of NO by CO in three-way catalytic converters. The validity of the theoretical results was verified by both... 

The RC1 reactor system temperature control can be operated in three different modes isothermal (temperature of the reactor contents is constant), isoperibolic (temperature of the jacket is constant), or adiabatic (reactor contents temperature equals the jacket temperature). Critical operational parameters can then be evaluated under conditions comparable to those used in practice on a large scale, and relationships can be made relative to enthalpies of reaction, reaction rate constants, product purity, and physical properties. Such information is meaningful provided effective heat transfer exists. The heat generation rate, qr, resulting from the chemical reactions and/or physical characteristic changes of the reactor contents, is obtained from the transferred and accumulated heats as represented by Equation (3-17) ... 

The choice of the method depends on the type of process. With electron beams the critical process parameters are beam energy, beam current, scanning factors and uniformity, beam pulse characteristics, and the configuration of the product being processed. 

The following case study illustrates how a product is scaled-up from 15 to 150 kg in equipment supplied by Niro pharma systems once one understands the critical process parameters used when scaling-up. 

Pilot phase development allows the formulator to evaluate critical process parameters of compression essential for trouble-free production. Typically, DOE are used to evaluate the effects of process variation on the resulting tablet... 

Process capability is defined as the studies used to determine the critical process parameters or operating variables that influence process output and the range of numerical data for critical process parameters that result in acceptable process output. If the capability of a process is properly delineated, the process should consistently stay within the defined limits of its critical process parameters and product characteristics [12],... 

Confirm critical process parameters and determine their effects on product quality attributes. 

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