Pocket Kits

These use a disc or a chart with coloured panels, each labelled with a figure. Normally, tablet reagents are added to the sample and the colour that develops is matched to a panel on the chart or disc.

Test Strips also use the principle of colour matching.  The reagents are already present on the test strip.  You simply dip them in the sample and compare the colour to a chart on the container.

The reasons for carrying out a test, the situation and the application all effect the choice of what test method is best for you.

For example, whilst accuracy and repeatability might be the most important factors in a modern laboratory.  Weight, speed of test, and the lack of requirement for electricity might be more important in a field expedition.

We refer to any method not using an electronic instrument as a visual method.  They fall in to four basic methods.

• Colour Matching
• Droplet or Tablet Counting
• Presence or Absence
• Development of Turbidity