Keep sources of ignition away for 30 minutes after all frost or fog has disappeared.

远离火源30分钟，直到所有的霜和雾都消失。

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Prevent electrostatic charge - sources of ignition should be kept well clear - fire extinguishers should be kept handy.

防止静电荷—远离火源—灭火器可随手取用。

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Cautions during transportation: Avoid exposing to air, sunlight, heating, shock, moisture, or any sources of ignition or other readily oxidizable materials.

运输中不得爆晒，受热，受潮，碰撞，应避免与易燃物质成其他容易氧化的物品混合储运。

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The area near an uphill incline is considered a collection point for fuel and ignition sources, and it's possible a piece of debris fell into the tinder-dry brush early Thursday and sparked the fire, Piranio said.

NPR: Cause Of California Wildfire Appears Accidental