1.   Make sure that the ventilation pipe is unobstructed, and that water can not run down the pipe into the house.

2.   Meanwhile a pair of kestrels has produced four young in a disused ventilation pipe in a raw materials store.

3.   These particular wells contained no water, he said, and part of his work involved sealing the ventilation pipe that emerged from the ground next to the wells.

4.   To make ventilation pipes, he used his pottery skills and created them out of ceramic.

5.   Entangled pieces of destroyed equipment, small heaps of scrap and chopped-off ventilation pipes dotted the sprawling facility.

6.   He said he heard accounts of prisoners corralled into chambers, showered with methane gas pumped in through ventilation pipes, and their corpses burned.

7.   In one, a flower thrusts defiantly through a straitjacket of ventilation pipes.

8.   She was imprisoned for four days in a plywood box buried underground and equipped with a ventilation pipe.

9.   Ventilation pipes and sluices were chopped off at several places.