Calibration company

Mapping of the sample surface of a chamber for the quality and quantity of illumination is the most important qualifying item for photostability testing. Little has been written or presented about it. AU manufacturers make claims but only a few present data, as they readily do for temperature and humidity. It is the purpose of this section to present what information does exist on the mapping of chambers and propose what should be done. To our knowledge, few of the calibration companies offer this service. 

Traceability. One of the requirements of laboratory accreditation by the United Kingdom Accreditation Service (UKAS) is that all measurements necessary for the proper performance of a test should be traceable, where possible, to national standards of measurement. In practice this means that some laboratory equipment such as a balance, thermometer or pressure gauge, for example, must be regularly calibrated by an accredited specialist calibration company, if accurate weight, temperature or pressure measurements are necessary for the test. 

Over the last decade some of the major oil companies have been using vast amounts of outcrop derived measurements to design and calibrate powerful computer models. These models are employed as tools to quantitatively describe reservoir distribution and flow behaviour within individual units. Hence this technique is not only important for the exploration phase but more so for the early assessment of production profiles. 

Within most companies, the responsibility for cahbrating measurement devices is delegated to a specific department. Often, this department may also be responsible for maintaining the measurement device. The specific cahbration procedures depend on the type of measurement device. The frequency of calibration is normally predetermined, but earlier action may be dic tated if the values from the measurement device become suspect. 

If the technical staff from the client company recognizes that a toller may be asked to perform new analyses and make operating decisions based upon the results, the client may help the toller develop the needed procedures and skills required to make these decisions. Typically a round robin laboratory qualification exercise will be performed. Samples of known standards and unknown concentrations of the materials to be analyzed for the toll will be prepared and sent to both laboratories. This can help ensure that equipment calibration is synchronized and that the toller is capable of performing accurate measurements. In some cases, the toller may be the party with the chemical, process, or synthesis specific expertise. 

The submitters used a transformer purchased from the Franklin Transformer Company, Minneapolis, Minnesota, for 25-30. It was provided with taps so that secondary voltages of 5500, 6600, 7700, 8800, 9900, and 11,000 could be obtained. These transformers do not always deliver the rated voltage and hence should be calibrated by actual measurement. The checkers used a luminous tube transformer obtained from the Jefferson Electric Company, Bellwood, Illinois, Cat. No. 721-411. Cap. 825 VA. Primary 115 V.A.C. 60 cycles. Secondary 15,000 V. 60 M.A. Price 19.60. The variable transformer used to regulate the voltage should be rated at 7.5 amperes and may be a Varitran, Adjustavolt, or Variac. 

A wet gas meter such as No. S-39465, E. H. Sargent and Company, is satisfactory. This meter need not be a permanent part of the apparatus. It is used only to calibrate the flowmeter. 

Another way of interpreting absolute risk estimates is through the use of benchmarks or goals. Consider a company that operates 50 chemical process facilities. It is determined (through other, purely qualitative means) that Plant A has exhibited acceptable safety performance over the years. A QRA is performed on Plant A, and the absolute estimates are established as calibration points, or benchmarks, for the rest of the firm s facilities. Over the years, QRAs are performed on other facilities to aid in making decisions about safety maintenance and improvement. As these studies are completed, the results are carefully scrutinized against the benchmark facility. The frequency/consequence estimates are not the only results compared—the lists of major risk contributors, the statistical risk importance of safety systems, and other types of QRA results are also compared. As more and more facility results are accumulated, resources are allocated to any plant areas that are out of line with respect to the benchmark facility. 

The appointed customer representative will need to spend some time with the customer to learn their ways, and understand their language, needs, and expectations. Hence if the native tongue of your staff is English and you do business with Swedish, Italian, and French companies you may need people who can speak these languages and who are familiar with the appropriate subject vocabulary. Beware, however, that in appointing such a person you choose wisely. It also has to be someone you can trust to represent your interests. You will need a means of calibrating this person so that he/she does not get carried away with enthusiasm and start to impose requirements that are no more than personal likes and dislikes. 

In some situations there may be no national standard against which to calibrate your devices. Colors and textures are two examples. If you face this situation, you should gather together a group of experts within your company or trade association and establish by investigation, experimentation, and debate what constitutes the standard. Having done this you should document the basis of your decisions and produce a device or number of devices which can be used to compare the product with the standard using visual, quantitative, or other means. 

The MWD total gamma ray tools cannot be calibrated in the standard pit, since they are too large. Their calibration in API units is difficult because it varies with the spectral content of the radiation. By spectral matching the MWD logs can be made to closely resemble the wireline logs. The logs which were recorded by the MWD companies in counts per second (cps) are now recorded in API units. 

Protein concentration can be determined using a method introduced by Bradford,4 which utilises Pierce reagent 23200 (Piece Chemical Company, Rockford, IL, USA) in combination with an acidic Coomassie Brilliant Blue G-250 solution to absorb at 595 nm when the reagent binds to the protein. A 20 mg/1 bovine serum albumin (Piece Chemical Company, Rockford, IL, USA) solution will be used to prepare a standard calibration curve for determination of protein concentration. The sample for analysis of SCP is initially homogenised or vibrated in a sonic system to break down the cell walls. 

In summary, to obtain 7% from a platinum resistance thermometer, one selects the range of interest, calibrates the thermometer at the fixed points specified for those ranges, and uses the appropriate function to calculate AW(Tw) to be used in equation (A2.5). Companies are available that perform these calibrations and provide tables of W T<)0) versus 790 that can be interpolated to give 7% for a measured W T90). 

The quality control unit in a cosmetics company supervised the processing of the weekly batch of shampoo by determining, among other parameters, the viscosity and the dry residue. Control charts showed nothing spectacular. (See Fig. 4.10, top.) The cusum charts were just as uneventful, except for that displaying the dry residue (Fig. 4.10, middle and bottom) The change in trend in the middle of the chart was unmistakable. Since the analytical method was very simple and well-proven, no change in laboratory personnel had taken place in the period, and the calibration of the balances was done on a weekly basis, suspicions turned elsewhere. A first hypothesis,... 

Enzyme Reference Serums. Several companies sell lyophilized or stabilized reference serums for the calibration of instruments and for quality control. The label values given for the enzymatic activity of these serums should never be taken at face value, as at times they may be quite erroneous (19,33). Also, these values should only be used for the assay with which they were standardized, as interconversion of activity from one method to another for the same enzyme may often lead to marked errors. For instance, it is not recommended that alkaline phosphatase expressed in Bodansky units be multiplied by a factor to convert it to the units of the Ring-Armstrong method, or any other method for that matter. 

But in order to understand what needs to be changed, we first need to understand the current situation. In order for a pharmaceutical company to use any analytical method for certifying the properties (efficacy, potency, etc.) of their products, the analytical method has to be validated. Validation , in the parlance of the FDA, is a far cry from what we usually call validation when developing a multivariate spectroscopic method. In fact, what we call validation in spectroscopic calibration (which usually means calculating an SEP, or an SECV) is a far cry from the dictionary definition of validate , which is to make legally valid , where valid is defined as having legal efficacy or force [11],... 

The submitters recommend calibrating the thermometer to ca. -78°C when immersed in a dry ice-acetone bath. The thermometer used for these runs (Catalog Z11,011-6) was purchased from Aldrich Chemical Company, Inc. Three different thermometers (two Fisher 15-035 and one Ertco X7048) were found that read from -86°C to -96°C when immersed In a dry ice-acetone bathl The checkers used a digital thermometer, model 450-ATT, purchased from OMEGA Engineering, Inc., Stamford, CT 05907. 

Novolac molecular weights were measured in THF at 35°C by high pressure size exclusion chromatography using a Waters Model 510 pump (flow rate=1.0 ml/min), 401 differential viscometer detector and a set of Dupont PSM 60 silanized columns. A universal calibration curve was obtained with a kit of 10 narrow molecular weight distribution, linear polystyrene standards from Toya Soda Company. Data acquisition and analysis were performed on an AT T 6312 computer using ASYST Unical 3.02 software supplied with the Viscotek instrument. 

Physical characterization of polymers is a common activity that research and development technologists at the Dow Chemical Company perform. A material property evaluation that is critical for most polymer systems is a tensile test. Many instruments such as an Instron test frame can perform a tensile test and, by using specialized software, can acquire and process data. Use of an extensometer eliminates calibration errors and allows the console to display strain and deformation in engineering units. Some common results from a tensile test are modulus, percent elongation, stress at break, and strain at yield. These data are then used to better understand the capabilities of the polymer system and in what end-use applications it may be used. 

This non-destructive technique is a very suitable tool for rapid in-line analysis of inorganic additives in food products (Price and Major, 1990 Anon, 1995). It can be readily used by non-skilled operators, and dry materials can be pressed into a pellet or simply poured into a sample cup. The principles of this technique related to food analysis are described by Pomeranz and Meloan (1994). A useful Internet site is http //www.xraysite.com, which includes information about different XRF instruments from various companies. Wavelength dispersive X-ray fluorescence (WD-XRF) or bench-top energy dispersive (ED-XRF) instruments are available. XRF is a comparative technique, thus a calibration curve needs to be established using food products of the same type as those to be... 

Measurements were made by first calibrating the pH probe using two buffer solutions at pH s of 7 and 10 supplied by Van Labs of Van Waters and Rogers Equipment Company. These solutions have been certified by the National Bureau of Standards to be accurate to + 0.01 pH unit at 25°C. This pH calibration was made with the probe inserted in buffer solution at the same temperature as the pH measurements were made. 

In this chapter, the principles and strategies behind HPLC calibration are described and illustrated with a case study of a company s revised calibration procedures and acceptance criteria. 

Calibration procedures are often similar to those used in the initial operational qualification of each module of the HPLC system. While each company s procedure might differ in the details, most share these common strategies. 

An analyst, a metrologist, or a qualified contractor can perform the calibration, though all must follow the company s prescribed standard operating procedure (SOP) and acceptance criteria. The cost effectiveness of using outside contractors or an internal metrology department is dependent on company size and the number of HPLC systems in the laboratory. 

In 2000 two major petrochemical companies installed process NMR systems on the feed streams to steam crackers in their production complexes where they provided feed forward stream characterization to the Spyro reactor models used to optimize the production processes. The analysis was comprised of PLS prediction of n-paraffins, /xo-paraffins, naphthenes, and aromatics calibrated to GC analysis (PINA) with speciation of C4-C10 for each of the hydrocarbon groups. Figure 10.22 shows typical NMR spectral variability for naphtha streams. Table 10.2 shows the PLS calibration performance obtained with cross validation for... 

Step 5 Off-line method or analyzer development and validation This step is simply standard analytical chemistry method development. For an analyzer that is to be used off-line, the method development work is generally done in an R D or analytical lab and then the analyzer is moved to where it will be used (QA/ QC lab, at-line manufacturing lab, etc.). For an analyzer that is to be used on-line, it may be possible to calibrate the analyzer off-line in a lab, or in situ in a lab reactor or a semiworks unit, and then move the analyzer to its on-line process location. Often, however, the on-line analyzer will need to be calibrated (or recalibrated) once it is in place (see Step 7). Off-line method development and validation generally includes method development and optimization, identification of appropriate check samples, method validation, and written documentation. Again, the form of the documentation (often called the method or the procedure ) is company-specific, but it typically includes principles behind the method, equipment needed, safety precautions, procedure steps, and validation results (method accuracy, precision, etc.). It is also useful to document here which approaches did not work, for the benefit of future workers. 

Near infra-red reflectance spectroscopy was first used by Norris and Hart [54] for the determination of moisture, oil and fat in cereal products. A number of instrument companies, notably Technicon, have developed commercial instruments. The instrument replaces a series of chemical procedures by a signal measurement in each of six infra-red regions and reference to a suitable computer calibration. Such an approach offers... 

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