The purpose of a check digit is to verify that the information on the barcode has been entered correctly. Your barcode scanner autmatically calculates the checksum by performing a series of mathematical operations on the digits that precede the check digit, and comparing the result of the calculation to the value of the check digit. If this comparison macthes, the barcode is valid. If it doesn't match, it could mean the barcode is worn out and the scanner is not able to read it properly or the barcode itself is defective.
To calculate the checksum, start with the total set to zero and scan the 13 digits from left to right:
These forms can be filled out anytime to place an order for barcode labels or patron cards. Generally, orders are be placed at the beginning of February, May, August, and November for any requests received in the previous three months. Should you need to expedite your order, once you fill in the order form email finance@olservice.ca to make special arrangements.
Orders are open to JASI and non-JASI libraries.