1.   According to the story, a man was torched when a spark from his phone ignited gas fumes while he was filling up.

2.   But as yet investigators have been unable to determine what ignited those fumes.

3.   But he said fire marshals were still trying to determine what ignited the fumes.

4.   But investigators still have not been able to determine what ignited the fumes.

5.   But the engineers have still not been able to determine what ignited the fumes.

6.   Carrying extra gasoline in that manner is illegal in many places because gas is so volatile that sparks can ignite its fumes.

7.   If the wiring is damaged, the board said, current could jump from one wire to the other and ignite fumes in the tanks.

8.   Once the tank is perforated, an errant spark can ignite the fumes, which are highly flammable and can quickly engulf anyone inside.

9.   The candle ignited fumes from gasoline the family stored in the home, and his head and hands were engulfed in a fireball.

10.   A halogen lamp ignited lacquer fumes and caused a flash fire that severely burned five workers at a high-rise condominium where several actors live.