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What does it mean to be one in a million?

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Not in the greeting card sense,

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in the scientific sense,

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where one part per million[br]is a unit of measurement.

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Parts per million counts the number[br]of units of one substance

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per one million units of another.

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It can measure concentrations when[br]a small amount makes a big difference.

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For example, a concentration of just[br]35 ppm of carbon monoxide in the air

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is poisonous to us.

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We encounter measurements like this[br]pretty often,

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but because it's hard to conceptualize[br]really large numbers,

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it's difficult to wrap our brain around[br]what one part per million really means.

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So here are nine helpful ways[br]to visualize it.

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If you had 11,363 pianos-worth [br]of piano keys,

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one of those keys would be about[br]one part per million.

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So would a single granule of sugar[br]among 273 sugar cubes,

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one second in eleven and a half days,

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or four dots in the painting,

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"A Sunday Afternoon on [br]the Island of La Grande Jatte."

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Your bath tub's capacity [br]is about 60 gallons,

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so seven drops of ink would be[br]one part per million.

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The English version of the Harry Potter[br]series has 1,084,170 words,

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which makes "hippogriff" on page 221[br]of "The Prisoner of Azkaban"

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a little less than one part per million.

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A million kernels of corn [br]is about 1,250 ears,

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so one kernel in that truckload[br]would be one part per million.

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There are 10 million bricks in[br]the Empire State Building,

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so one part per million [br]would be a pile of just ten.

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And finally, 100 people worked together[br]to animate this video.

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Collectively, they have about 10 million[br]hairs on their heads.

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Pluck ten of those hairs,[br]and you have one in a million.