5 factors that can easily affect experimental results

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1 Carelessness in inspection and calculation: Inspection is a process that requires concentration; the slightest carelessness can lead to errors. With the widespread use of mobile phones, it is very common for inspectors to answer their phones during the inspection process or while calculating data after the inspection. Cases of inspection errors resulting from such behavior and other acts of carelessness occur from time to time. Testing errors caused by carelessness during the inspection and calculation processes are not common, but once they occur, they will directly lead to incorrect test results. 2. It is not sensitive to suspicious data. Generally speaking, each substance has its own characteristics, and its detection values should fall within a certain range; for example, the thermal conductivity of polystyrene boards cannot be 0, and building exterior windows made from different aluminum alloy profiles and ordinary single-layer glass cannot meet the requirements of insulating windows. When inspectors or those who approve inspection reports detect suspicious data that does not conform to normal patterns, they should recheck such data to determine whether there is a problem with the instruments and equipment or an error in the inspector’s operations. WeChat official account: Laboratory ISO17025 Reminder. Being able to correctly determine whether data is suspicious relies on extensive knowledge of the theories related to the products being tested as well as practical testing experience. This is also a fundamental skill that a competent tester and someone responsible for reviewing and approving test reports should possess. Without long-term training, it is impossible to detect suspicious test data sensitively. There is a deviation in the handling of the 3 critical values. During the testing process, the presence of measurement uncertainties can lead to deviations in the determination of whether a test result falls within the critical values. For example, in terms of coating thickness, for ordinary aluminum-plastic panels used for decoration, since the coating thickness is relatively small, accurate calibration of the \"0\" point during measurement is particularly important for products that are at the critical threshold specified by standards. If zero adjustment is performed using a standard substrate, a deviation of (1–2) um may occur, which could cause the product to slide from the \"qualified\" category toward the \"unqualified\" category. For ordinary decorative aluminum-plastic panels, the coating can be removed from the product, and adjustments can be made on the exposed substrate to ensure the accuracy and objectivity of the results. Therefore, for test results with critical values, multiple comparison tests should be conducted using different testers or instrumentation to ensure that the test results are scientific and fair. There are misunderstandings regarding 4 pairs of standards. Inspection is a highly precise task, and incorrect understanding and application of the standards by some inspectors directly affects the accuracy of the inspection results. For example, in the testing of ordinary decorative panels with fluorocarbon coatings, GB/T22412-2008 stipulates that the testing of the coating properties of such aluminum-plastic panels should be carried out in accordance with GB/T17748-2008. In tests, it is easy to have a preconceived notion of it as merely an \"ordinary decorative material,\" ignoring the fact that it is a fluorocarbon coating; this leads to the use of incorrect testing standards, ultimately rendering the test results invalid. 5. New inspectors lack effective supervision. In recent years, many testing agencies have expanded on a large scale, resulting in a severe shortage of experienced inspectors. In some laboratories, new employees start working on testing tasks after only a few months of training; such inspectors are not very proficient in their work, lack sensitivity to abnormal data, and there is no effective supervision over them, which increases the likelihood of errors on their part compared to more experienced staff. Therefore, new inspectors with limited experience and without supervision pose a higher potential risk. Therefore, in accordance with the requirements of the laboratory accreditation evaluation criteria, sufficient supervision should be provided for personnel who are in training. When the laboratory employs new staff or those changing roles, in addition to assessing their competence for the job, laboratory supervisors should exercise enhanced oversight during testing to prevent testing errors.