Since all print cartridge manufacturers used to use different testing methods, comparing suppliers had never been an easy thing to do.

In recent years this situation has changed. Requirements for tests of monochrome inkjet cartridges put in place by the International Standards Organization (ISO) were adopted by most of the companies that supply ink in the summer of 2004.

The ISO is recognized for developing standards for many different industries to offer a standardized, unbiased way of comparing or rating products.

Printer cartridge standards allow you to compare ink manufacturers’ products. Since the same methods are used to ascertain the yield derived from cartridges, they are much easier to compare against each other.

The following are the things that are specified in the ISO standard:

- Default settings must be used when printing test examples.

- Temperature is strictly controlled while test examples are being printed.

- Both the cartridges and the printers used for testing must be available to the average consumer

- In order to assure that tests are valid, nine cartridges of each type must be tested.

- Since a certain printer could unfairly affect test results, three cartridges have to be tested with three different printers.

Aside from raw numbers, you should also consider some other things when deciding on your ink supplier. These things include delivery, reliability, and general quality.

Keeping notes on your own printing results is another way to decide which ink suppliers prove themselves to be deserving of your purchase.