This course in the APHLIS series on postharvest loss measurements introduces you to the creation and use of visual scales to facilitate and speed up the estimation of losses during storage.
The course explains how to use a visual scale and in what context; how to define the quality classes that make up the visual scale; how to create examples of these quality classes and present them in transparent boxes, dishes or bags for use in the field.
To collect the local information needed to create the visual scale you will need to work with informants. Your visual scale will need to be used by the enumerators once you have trained them.
Finally, the course describes the data to be recorded at each stage.