“Be Prepared” Isn’t Just for Boy Scouts: The Importance of Practice in Field Testing

Aug. 27, 2012

Hach Tip of the Month

Adapted from Dan Kroll

One of the most important aspects of preparedness for a water contamination emergency is the development of adequate field analysis proficiency. Having a good understanding of the analytical procedures before attempting them in the field is a sensible tactic. Many analytical procedures have subtle nuances and can be very technique dependent. It is important not only to recognize the intricacies of the procedure but also be aware of the underlying chemistry or biology involved. An understanding of the science involved and possible issues that could arise (interfering substances, environmental conditions such as temperature, light, etc.) can be helpful. The ability to recognize potential problems in performing a method and being able to address them when they arise can vastly improve the accuracy of procedures performed in the field.

Beyond having an intellectual understanding of the procedure, the old adage of practice makes perfect is aptly applied in this situation. Dry runs of the testing procedure should be practiced in as close to field-like conditions as possible, including aspects such as manipulation of equipment and chemistries when wearing protective equipment.

Many procedures also exhibit procedural sensitivity to individual operators'' technique. Practice of non-instrumental procedures that rely upon the matching of colors or the recognition of a colorimetric endpoint such as in a titration should be practiced with diligence. Many people have difficulty in recognizing specific color (e.g. red–green colorblindness) and even though manufacturers try to calibrate to an average ability to match and recognize colors, not all individual diversity can be taken into account.

The choice of test kit can also be tailored to the user''s skill level. Fortunately, for most parameters of common interest, there are a variety of analytical methodologies designed to serve the various user communities. Method difficulty ranges from simple-to- use test strips to field portable meters. It is important, when making a choice of which analytical method to deploy in the field, to be well aware of the competence of the end-user. Even highly trained and proficient operators can make mistakes when trying to operate equipment or perform procedures in emergency situations. Field-testing in emergency situations can be quite tense and the less demanding the procedure is, the better. In the end, just remember that while practice may not make you perfect, it sure can help.