How about 'volume', what is 'big' or 'large'

[FredMark]

There are several tags that a litter picker can choose to tell what he found that have something like 'small' or 'large'.

For instance:
Food --> Crisp small
Food --> Crisp large.

or

Dumping --> small / medium / large

What do we plan to do with this.

Because in the Netherlands we do have small crisp bags and large bags. But what we call large, is a small bag in the USA.
So if i use the tag 'big' and somebody in the USA downloads the data, he has got a different perception of the data than if a Dutch user downloads the same data. That can't be right.
So how do we make it move in-ambigious what small or large is?

(Same for dumping. If i found 6 bags with litter in nature, i call it a big dumping. However, i have seen pictures on facebook where inhabitants would be very happy if they found only 6 bags and they would call it a very small dumping).