Perhaps not the best situation to be in, but sometimes it is necessary to calibrate a meter whilst out in the field. The following types of Hanna meter can all be calibrated by the user whilst 'out and about':-
When you purchase your meter from this web site, you will see a list of highly recommended accessories. These will always include the calibration solutions or reference solutions that are needed to perform a field calibration.
The exception to this, is our new range of colorimeters which allow you to not only check the calibration, but to actually calibrate. As these are so unique in the market, we include the primary reference standards which are required to perform calibration within the price, so with these particular meters, there is no need to purchase extra standards until such time as you need them.