WASHINGTON — The National Institute of Standards and Technology is once again promoting its 2010 video that shows how fast a dry Christmas tree can be set ablaze, versus a well-watered Christmas tree.

According to NIST, the moisture content of the trees in the video is determined based on the dry weight of the needles, which “act like sponges so they can hold water that exceeds 100 percent of the dry weight of the needle.”

The tree on the left has more than 100 percent moisture content. The tree on the right has less than 10 percent moisture content. Both are Fraser firs.

The Anne Arundel County Fire Department offers the following tips for fire safety this holiday season:

Selecting your tree

  • Buy a fresh tree with green needles that do not fall off when touched
  • Make a fresh, half-inch cut from the base of the trunk before putting the tree in the stand
  • Place the tree three feet away from heat sources
  • If you get an artificial tree, look for a UL or FM list mark, indicating fire retardance
  • Don’t block exits

Watering your tree

  • Use 1 quart of water per inch of the tree trunk’s diameter (3-inch trunk = 3 quarts of water)

Decorating your tree

  • Use UL or FM listed lights
  • Check lights for damage
  • Don’t use real candles
  • Read manufacturer’s instructions about how many lights you can connect together, but limit to three string sets
  • Turn off lights at night or when you’re not home

Disposing of your tree

  • When the needles begin to fall, remove your tree from the house and take it to the curb (or another spot far away from the home)

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