how to check if chimney needs sweeping

[vw754]

Is there anyway i can check (prior to fitting a new gas fire) if the chimney needs sweeping, i.e i was told that there is some way of smoke testing or putting a newspaper infront of the opening to see if it tries to suck up the paper ??????? :?

[htg engineer]

If t has ever been used for solid fuel, or has not been used for a number of years - it needs sweeping.

htg