Q. Can salat be read anywhere, without a mat? For example on Saturday we visited a sick friend at a hospital and the group read salat in the waiting area, making sajda on the bare carpet where the public access.
A. Once the area on which Salaah is to be performed is clean/pure, then it is allowed to perform Salaah without a mat. If it is dirty/not clean, then you need to put a mat. With respect to what you have asked about, seeing that it is an area where people are constantly walking upon with their shoes, then they should have spread a mat for salaah. However, seeing that there was no apparent impurity, the Salaah will be accepted.
And Allah knows best.
Mufti Waseem Khan