There is all kinds of test literature telling us that back pack vacuums, besides being faster, also do a better job of lifting soil from carpets than upright vacuums in commercial cleaning environments.
Noone believes it – no beater bar ! – can’t be true !
Including my janitorial operations staff – until ……..
I split our lobby in half one winters day when there was plenty of sand in the carpet.
I vacuumed (had them vacuum actually) 1/2 with the back pack and the other 1/2 with the upright.
Then I went over each of the two just vacuumed areas with the OTHER vacuum.
No sound of sand being picked up by the upright – the back pack apparently got it all.
Lots of rattling in the back pack tho – apparently it was picking up stuff the upright had missed.
Lesson learned and operations staff convinced.