Is Contamination A Random Or Systematic Error
Contents |
of causes of random errors are: electronic noise in the circuit of an electrical instrument, irregular changes in the heat loss rate from a solar collector random error due to changes in the wind. Random errors often have a Gaussian how to reduce random error normal distribution (see Fig. 2). In such cases statistical methods may be used to analyze the data. The
Systematic Error Calculation
mean m of a number of measurements of the same quantity is the best estimate of that quantity, and the standard deviation s of the measurements shows the accuracy of
How To Reduce Systematic Error
the estimate. The standard error of the estimate m is s/sqrt(n), where n is the number of measurements. Fig. 2. The Gaussian normal distribution. m = mean of measurements. s = standard deviation of measurements. 68% of the measurements lie in the interval m - s < x < m + s; 95% lie within m - 2s < types of errors in physics x < m + 2s; and 99.7% lie within m - 3s < x < m + 3s. The precision of a measurement is how close a number of measurements of the same quantity agree with each other. The precision is limited by the random errors. It may usually be determined by repeating the measurements. Systematic Errors Systematic errors in experimental observations usually come from the measuring instruments. They may occur because: there is something wrong with the instrument or its data handling system, or because the instrument is wrongly used by the experimenter. Two types of systematic error can occur with instruments having a linear response: Offset or zero setting error in which the instrument does not read zero when the quantity to be measured is zero. Multiplier or scale factor error in which the instrument consistently reads changes in the quantity to be measured greater or less than the actual changes. These errors are shown in Fig. 1. Systematic errors also occur with non-linear instruments when the calibration of the instrument is not known c
result in inconsistent values. Precision
Random Error Examples Physics
produces consistent results but not necessarily accurate results Errors types of errors in measurement in precision are usually systemic errors. Systemic errors are due to defective equipment zero error operation such as defective weighing equipment Operator errors are caused by the operator (i.e. human error). Examples producing errors securing an unrepresentative http://www.physics.umd.edu/courses/Phys276/Hill/Information/Notes/ErrorAnalysis.html sample due to - poor dispersion and integration of additions especially in musts with skins in large tanks with additions of undissolved powdered forms contamination of sample by - contaminated equipment inaccurate preparation of standard solutions - inaccurate dilutions inaccurate volume/weight measurements inaccurate standardisations http://www.monashscientific.com.au/Errors.htm inaccurate measures of volume, weight etc. contaminations Faulty equipment usage - loss of SO2 being aspirated through loose fitting joints incorrect aspiration/flow rate (see flow rate ) decrease/increase in 15 min. aspiration time General - incorrect use or reading of volumetric glassware. incorrect labeling contamination of solutions, glassware and/or equipment deterioration of solutions and/or solution strengths 0.03% Hydrogen peroxide (H2O2) soln. needs to be prepare daily (see preparation) 0.01M NaOH needs to be prepared daily with 0.1 M NaOH needing protection and standardisation. Errors in mathematical calculations Contamination of solutions Contamination of stock solutions should be avoided by pouring an estimated working volume of stock solution into a separate container (e.g 100 ml beaker). Discard working solutions after use. Cross contamination of solutions can be avoided by working systematically.
Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. If you continue browsing the site, you agree to the use of cookies on this website. See our Privacy Policy and User http://www.slideshare.net/skvemula/laboratory-errors Agreement for details. SlideShare Explore Search You Upload Login Signup Home Technology Education More Topics For Uploaders Get Started Tips & Tricks Tools Laboratory Errors Upcoming SlideShare Loading in …5 × 1 1 of 30 Like this https://books.google.com/books?id=Z6xxWQ2CTDcC&pg=PA194&lpg=PA194&dq=is+contamination+a+random+or+systematic+error&source=bl&ots=AXar_TRwrF&sig=-R3d1hM3V6G2NPh2h0Jb9LWK8q8&hl=en&sa=X&ved=0ahUKEwiy6PeDwd_PAhUIxoMKHZTmCIo presentation? Why not share! Share Email LAB ERRORS byVikash Gautam 5317views Analytical and post analytical erro... byHanisha Erica Vil... 2046views Laboratory errors in medical practice byMedicineBSMMU 2321views 5 preanalytical factors affecting c... byDamietta University 25798views systematic error Pre analytical errors byNasir Nazeer 3483views Understand the importance of each s... bySathish Vemula 4433views Share SlideShare Facebook Twitter LinkedIn Google+ Email Email sent successfully! Embed Size (px) Start on Show related SlideShares at end WordPress Shortcode Link Laboratory Errors 11,277 views Share Like Sathish Vemula, Manager - Quality Assurance (Laboratory Compliance) at Aurobindo Pharma Limited Follow 0 0 0 Published on Dec 16, 2013 Analytical Laboratory Errors. ... Published in: Health how to reduce & Medicine, Technology 2 Comments 14 Likes Statistics Notes Full Name Comment goes here. 12 hours ago Delete Reply Spam Block Are you sure you want to Yes No Your message goes here Post Aime Gapelba , Laboratory and pharmaceutical Scientist chez RMSI Medical Solutions at RMSI Medical Solutions All effort should be made to minimize analytical errors, and even more efforts are needed for pre- and post analytical errors. 2 months ago Reply Are you sure you want to Yes No Your message goes here Litegebew yitayeh , Laboratory and Pathology Manager at GAMBY TEACHING GENERAL HOSPITAL at GAMBY TEACHING GENERAL HOSPITAL ችግር መፍትሔ ይፈልጋል 9 months ago Reply Are you sure you want to Yes No Your message goes here Livija Šimičević , Medical biochemistry and laboratory medicine resident at University Hospital Centre Zagreb 3 weeks ago vijaya lakshmi , associate professor at bapatla college of pharmacy at bapatla college of pharmacy 3 months ago Saher Sous , Lab Tech at Alwattani Hospital Lab at Alwattani Hospital Lab 4 months ago Mohammed Adem at Yahoo 8 months ago Litegebew yitayeh , Laboratory and Pathology Manager at GAMBY TEACHING GENERAL HOSPITAL at GAMBY TEACHING GENERAL HOSPITAL 9 months ago Show More No Downloads Views Total views 11,277 On SlideShare 0 From Embeds 0 Number of Embeds 24
from GoogleSign inHidden fieldsBooksbooks.google.com - A synthesis of years of interdisciplinary research and practice, the second edition of this bestseller continues to serve as a primary resource for information on the assessment, remediation, and control of contamination on and below the ground surface.Practical Handbook of Soil, Vadose Zone, and Ground-Water...https://books.google.com/books/about/Practical_Handbook_of_Soil_Vadose_Zone_a.html?id=Z6xxWQ2CTDcC&utm_source=gb-gplus-sharePractical Handbook of Soil, Vadose Zone, and Ground-Water ContaminationMy libraryHelpAdvanced Book SearchBuy eBook - $220.00Get this book in printCRC PressAmazon.comBarnes&Noble.comBooks-A-MillionIndieBoundAll sellers»Practical Handbook of Soil, Vadose Zone, and Ground-Water Contamination: Assessment, Prevention, and Remediation, Second EditionJ. Russell Boulding, Jon S. GinnCRC Press, Apr 19, 2016 - Technology & Engineering - 728 pages 1 Reviewhttps://books.google.com/books/about/Practical_Handbook_of_Soil_Vadose_Zone_a.html?id=Z6xxWQ2CTDcCA synthesis of years of interdisciplinary research and practice, the second edition of this bestseller continues to serve as a primary resource for information on the assessment, remediation, and control of contamination on and below the ground surface.Practical Handbook of Soil, Vadose Zone, and Ground-Water Contamination: Assessment, Prevention, and Remediation, Second Edition includes important new developments in site characterization and soil and ground water remediation that have appeared since 1995. Presented in an easy-to-read style, this book serves as a comprehensive guide for conducting complex site investigations and identifying methods for effective soil and ground water cleanup.Remediation engineers, ground water and soil scientists, regulatory personnel, researchers, and field investigators can access the latest data and summary tables to illustrate key advantages and disadvantages of various remediation methods. Preview this book » What people are saying-Write a reviewUser Review - Flag as inappropriategroundwater hydrologySelected pagesPage 8Page 12Page 7Title PageTable of ContentsContentsPart II167 Part III437 Appendix A575 Appendix B597 Appendix C615 Appendix D629 Appendix E659 Appendix F663 Index679 Copyright Other editions - View allPractical Handbook of Soil, Vadose Zone, and Ground-Water Contamin