Bright idea could keep you safe if an earthquake or typhoon leaves you without electricity.

Japan is an extremely safe place, what with violent crime being almost nonexistent, even in major cities. However, due to the country’s climate and geography, there are a number of situations such as earthquakes, typhoons, blizzards, and landslides that one needs to be prepared for.

The Tokyo Metropolitan Police Department’s duties include helping to keep people safe during such natural disasters, and its Disaster Response Division regularly shares information and advice through its official Twitter account. Recently, it shared a clever and easy way to light up your surroundings should you need to make to make it through a night without electricity after a disaster knocks the power out.

“You keep a flashlight in your emergency preparation kit, right? There’s an easy way to turn it into a lantern,” the tweet begins. “All you have to do is place a plastic bottle, filled with water, atop the flashlight. The light will diffuse, allowing you to illuminate the surrounding area.”

If your flashlight is too small to balance with a bottle on top of it, you can also place the flashlight inside a cup or any other container, then put the bottle atop that. Since there’s no fire involved, this is also safer than using candles or gas lanterns if aftershocks or other conditions mean your lantern could tip over. While a clear bottle of plain water works best, colored drinks or translucent bottles can also provide some light in the darkness.

Speaking of bottles, should you have any spare empties lying around, the Disaster Response Division says you can refurbish it into a set of spoons if you need eating utensils. Using scissors or a utility knife, simply slice off a spoon-shaped cutout from the bottle (as marked by the blue lines in the photograph below).

Just make sure you keep at least one bottle uncut to use for a lantern.

Source, featured image: Twitter/@MPD_bousai

Follow Casey on Twitter, where he’s thinking he also could have used this idea to spruce up his bachelor bunker back in the day.