EHS requires the chemical inventory to identify the exact room number the chemical is kept.
In the case of the open lab bench room #4400, the room number should be followed with the bench number that the chemical is kept (eg. 4400-1).
This chemical database has a related room database to which you can add rooms that then show in the Room dropdown list when adding or editing a chemical. You will see a tab for accessing the ability to add rooms as needed.
You may need to refresh the browser page for any changes made in the dropdown list editors to be reflected back into the main chemcal inventory editor.