1.   Earlier this week, the difficulty forced the Mir crew to begin igniting lithium perchlorate candles to generate oxygen for breathing.

2.   It too had shut down in the wake of the accident, forcing the three men to rely on the combustion of lithium perchlorate candles to generate electricity.

3.   Linenger and his cosmonaut hosts have had to rely on the controlled combustion of lithium perchlorate candles to generate breathing oxygen.

4.   The Mir crew is relying on the controlled combustion of lithium perchlorate candles to generate oxygen for breathing.

5.   The station crew had been periodically igniting lithium perchlorate candles to produce breathing oxygen.

6.   The station crew ignited lithium perchlorate candles to generate oxygen, Campion said.

7.   The three men will rely on the combustion of three lithium perchlorate candles each day to generate sufficient amounts of fresh breathing air.

8.   The station crew also replaced an igniter that triggers the combustion of lithium perchlorate candles, the backup system.

9.   To compensate, the Mir crew is burning one lithium perchlorate candle each day to generate more breathing oxygen.