There's no doubt that "burra" means a clothes rack. Apart from the fact that it has to be that from the context, since it is clearly something on which the customer can see clothes hanging, an image search for "burra" + "ropa" puts it beyond doubt:

https://www.google.es/search?um=1&es_sm=93&biw=1024&bih=653&...

For that matter, it also seems to be called a "burro":
https://www.google.es/search?um=1&es_sm=93&biw=1024&bih=653&...

A "paraban", it seems, can be a clothes rack, though it can also be a screen (as Helena's references show). Anyway, the term here is apparently burra.

I can't find any references at all to "burra(s) de suelo" or "en suelo". But it's pretty obvious that it refers to free-standing racks on the shop floor. As for "un perimetral", again I can't find any clear indication of what it is, but from the context I think it must mean a rack or other display unit with clothes hanging on it round the perimeter of the shop floor: in other words, a wall rack or wall unit. Like the "burra de suelo" it is something on which the customer can see clothes hanging.

So for "burra de suelo" I think we'll have to specify "floor rack", to distinguish it from the "perimetral". It'll go something like: "when a customer approaches a wall display or floor rack".

"Floor rack" is a valid term:

"The shop also does alterations, but if you're in a hurry there are rows of ready-to-wear suits at bargain prices on the many floor racks."
http://www.telegraph.co.uk/travel/destinations/northamerica/...