In the German firms it is "street noise" which is primarily responsible, whilst the French travel agencies studied were further away from the street (in passageways, inside courtyards, higher storeys, etc), so that this source was of only secondary importance, but telephone conversations by colleagues were mentioned much more frequently.
Ασχετα με το επίπεδο τεχνολογίας, το σημαντικότερο εργαλείο και στις δύο χώρες ήταν το τηλέφωνο.