Are the boxes made out of non flammable material?

这些盒子是否用非易燃物料制成？

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Remove flammable material around your heating source.

移除供暖热源附近的易燃材料。

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High winds and flammable material on scaffolding AIDS flames.

狂风和脚手架上的易燃材料增大了火势。

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The flames at that point were barely noticeable, just tiny tongues lapping at the flammable material.

NPR: No Alarm, Only 1 Exit In Brazil Nightclub Fire

That truck over there, with "highly flammable material" written on it What a disaster if it were to explode!

BBC: Viewpoint: Bad case of Baghdadophobia

But some building experts say that many of those towers are sheathed in a highly flammable material that puts occupants at risk.

BBC: 'Towering inferno' fears for Gulf's high-rise blocks