The shoreline samples

Text: an original contemporary personal account-style practice extract.

At the start of the shoreline survey, the coordinator gave us six empty sample pots and a list of six locations. Each pot had a letter printed on its side. Before collecting anything, I copied the matching location code onto each lid and asked my partner to read it back to me. We carried the pots upright in a padded box. When we returned, I wiped sand from the outside of each pot but left every lid closed for the coordinator to open.

From the extract, identify one action the writer took to reduce the risk of a sample being assigned to the wrong location.