Basic Quality Control Checks

The online version of this chapter (doi 10.1007/978-l-4471-4962-0 4) conteiins supplementary material, which is available to authorized users. 

Please note some of the figures within this chapter have been reproduced in full size online at Extra Materials (extras.springencom) for ease of viewing 

The QRS complex The ST segment The T wave The QT interval Additional features 

Prior to interpreting the ECG it is helpful to perform some quick quality control checks (As discussed in Chap. 3). A brief check should ensure the ECG was recorded under normal parameters, and if not that you as the interpreter are aware of any changes made during the recording process. Checks should include  

The next thing to determine is the heart rate. Many ECG machines will work this out automatically and display this information on the ECG. It is however important that 

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Over the twentieth century, the mbber industry has developed special rheometers, essentially factory floor instmments either for checking process regularity or for quality control purposes, for instance, the well-known Mooney rheometer (1931), the oscillating disk rheometer (1962), and the rotorless rheometer (1976). All those instmments basically perform simple drag flow measurements but they share a common feature During the test, the sample is maintained in a closed cavity, under pressure, a practice intuitively considered essential for avoiding any wall slip effects. Indeed it has... 

Note This experiment assumes that a permanent log and a quality control chart are constantly maintained for each analytical balance in use in the laboratory. Each day you use a given analytical balance and log in with your name and date. The following calibration check should be performed weekly on all balances. If, according to the log, the calibration of the balance you want to use has not been checked in over a week, perform this procedure. Review Section 3.3 for basic information concerning the analytical balance. 

Analytical measurements should be made with properly tested and documented procedures. These procedures should utilise controls and calibration steps to minimise random and systematic errors. There are basically two types of controls (a) those used to determine whether or not an analytical procedure is in statistical control, and (b) those used to determine whether or not an analyte of interest is present in a studied population but not in a similar control population. The purpose of calibration is to minimise bias in the measurement process. Calibration or standardisation critically depends upon the quality of the chemicals in the standard solutions and the care exercised in their preparation. Another important factor is the stability of these standards once they are prepared. Calibration check standards should be freshly prepared frequently, depending on their stability (Keith, 1991). No data should be reported beyond the range of calibration of the methodology. Appropriate quality control samples and experiments must be included to verify that interferences are not present with the analytes of interest, or, if they are, that they be removed or accommodated. 

The Technical Services function of AOCS establishes, revises, and annually updates AOCS Methods, the Official Methods and Recommenced Practices of the American Oil Chemists Society22 for fats, oils, and soap technology Spanish AOCS Methods, a Spanish translation of the more commonly used AOCS Methods and Physical and Chemical Characteristics of Oils, Fats and Waxes. Leaders of the methods development committees coordinate closely with AOAC International (formerly the Association of Official Analytical Chemists). AOCS Methods are recognized as Official Methods in US FDA activities and when litigation becomes necessary in industry trade. Additionally, the Technical Services function operates a Laboratory Proficiency Program (formerly the Smalley Check Sample Program) and oversees distribution and statistical analysis of 30 different series of basic laboratory quality assur-ance/quality control test samples. Certification as AOCS Approved Chemists, or as AOCS... 

Active control implies that the "paper on glass" documents are no longer static. Data may be collected automatically so that only a few of the data entries are manually entered, most of them are entered through automatic data capture, possibly with a border value check and some kind of compliance enforcement. This requires a certain level of integration with physical data equipment, such as control systems, instruments, bar code readers and so on, which may prevent common errors from manual data entry and additionally provide enforcement of basic quality requirements. Active control requires the paperless system to be a true application that actively assists the user s data entry with automatic data collection and possibly interfaces to other systems. 

Corrective adion is the term used to describe the identification and remediation of errors occurring within an analysis. Corrective action is necessary whenever the result of the analysis of any quality control sample falls outside of the established control limits. The steps involved may include simple things like checking calculations of basic instrument maintenance, or it may involve more complicated actions like major instrument repair. Whatever the source of error, it must be identified and corrected (and a Corrective Action Report (CAR) must be completed. CARs should be kept on file by the laboratory. 

Incoming raw materials, specifically the matrix constituents and the fibre rovings and mats, should be inspected. Basic inspection includes checking the delivery notes and the labels of containers when the materials arrive. Visual inspection of raw materials is also recommended resins can be inspected for colour and the presence of contamination and gel particles (Evans, 2000) reinforcements can be checked for the presence of knots in the rovings, while simple mass measurements can be made for mats or fabrics. Some pultrusion companies have quality control and/or research and development laboratories where material characterisation tests can be performed (most often such control is executed by raw material suppliers). Fibre reinforcements can be subjected to tensile tests. The moisture content of the constituents (particularly the reinforcements and the fillers) can also be determined. The quality of incoming resins can be tested by means of thermal analysers (resin reactivity) and viscometers (resin viscosity and thixotropic index) (Owens Coming, 2003). 

Traditionally in manufacturing the concept of quality was conformance to certain dimensions and specifications, the clichd being fitness for purpose . Quality control was achieved by inspection and supervision. Inspection is the most basic approach to quality. The aim being for an inspector to detect, and if sufficiently serious to reject before despatch if a product deviates from a set standard. Inspection will at least provide the customer with an acceptable product. Quality inspection is an expensive method of achieving a basic level of quality. It requires the employment of people to check on the operators. Inspection and supervision does not add value to a product, but does add to the cost ... 

This is an extremely important aspect of the whole exercise. The basic purpose of all checks and controls is to reduce reworking, reprocessing, failures or rejections during the work process with a view to produce a product of the required quality and hence minimize cost for better financial returns. A high-cost input not commensurate with the type of the product may defeat the basic puipose of adopting such a system. 

The method employed is very similar to that used for processing palm oil. The basic technique is to pretreat the oil with an acid solution and then bleach the mixture with activated clay. This procedure requires strict control of the feed stock quality as well as frequent checks on the bleached oil quality. 

On-line sensors are used as part of the CIP system to check aspects such as the concentration and quality of the caustic cleaning fluid. Conductivity metres are fitted within the CIP set itself to evaluate the detergent concentration and control a dosing pump to top up the detergent as required. From an overall automation perspective, all the basic parameters for flow, temperature and time are each controlled and monitored as part of the CIP system. 

Quality assurance includes the setting of standards with documentation and also includes the documentation of the method of checking against the specified standards. Quality assurance can also include a third-party approval from a recognized authority, such as ISO. With quality assurance, inspection and control are still the basic approach, but in addition one would also expect a comprehensive quality manual jointly agreed by the supplier and the purchaser. 

Northern Ireland and the hill areas of England and Wales where substantial seed potato enterprises still continue. The main advantages of these areas ate that the low temperatiues and strong winds keep aphid populations in check. This means that the severe virus diseases (leaf roll and the mosaics) which are spread from diseased to healthy plants by aphids, are less likely to occur. However, recent advances in aphid control and concerns over the quality of seed from some traditional areas have seen successful seed production extended to some of the English arable areas as a profitable break in predominantly cereal and break crop rotations. As with other forms of seed production the certifying authority in England and Wales is FERA, for Scotland SASA (Science and Advice for Scottish Agriculture) and DARD in Northern Ireland. In all cases the same basic Seed Potato Classification Scheme (SPCS) obtains. 

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