ARCHIVED REPORTS_2009_15 - Laserfiche WebLink

Home Browse Search

p i meter to sound. This point is usually cieacly visible on the probe. If it is not visible it should .1 ted by dipping the probe into a water container where the contact can be clearly seen, then- ) ked. The total-length of the water level meter should correspond with the length of the measuring tape. In addition, the individual its on the cable should correspond with the co ct footage. If the cable does not match the measuring tape then the diff ce(If consistent) should be calculated. as a pe tage, (i.e.; 00 foot cable measures 102. feel = 98%). All Measurements with the cable should-thea be multiplied by 0.98 to correct for the r. °the individual footage marks are not placed correctly and arc not consistent in their deviation, the iaitrument should be replaced. If the water level indicator is constructed of a cable then cal'bration will be peifOnnedf once per Year. If there is a discrepancy, the conversion factor will be marked directly on the ' cut. Water level indicators constructed of tape are more subject to stretching and should be c aMrated every 6 months and marked with the appropriate conversion.. Calibration data for each instm ent will.be_recorded and keptin-a binder-at the:office forfuture. -. reference. The most recent calibmdon results will also be recorded in the technicians field nates.. - Therc is.no specific form for water level indicator calibration. 0i off l�lcter . pH is.subject to significant variations due to temperature, buffering capacitor of the water, and instrument drift.-For diis reason pH meters must be-calibratedbefore and after -s-Uppiing on each.. day and at least once more du3ing the day. To calibrate a pH meter,the insMment -reading is 4usted to read cv y for solutions with a standard pH.. Standard solutions aremixed d according to packgige ' 'oris,-for each wmpling-event' 'Standard solutions or powders for pH 4,7, and 10 are commercially fe, Theft standards P urchased fresh and'discarded afler sheM fife Shelf aves vary dq=ding on the brand of standards used. If p solution is used,the cxpirafion d.1ft of the solution will be noted on the canration log. Although differ=t brands of pH MCV= vary, ealt`bration PmcedUrCS are sfirtilar for all of them gencialized calibration proceduie follows: f. Turn on the instrument,check the battery,and allow to warm up if n_ec ,. t = 93849»FO tt23 t OR32$ A-2 Tt:ty 14,200 copyrwx 2M xkW414a.tae.