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Rails are pre-stressed to help
them resist the effects of high

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temperatures. In Britain,

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our rails have a stress-free
temperature of 27 degrees -

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halfway between the coldest and
hottest we expect our rails to

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get in the UK.

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We also tension our overhead
line equipment to cope with

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heat. When the air
temperature reaches 30 degrees Celsius,

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the temperature on the rail
can be up to 20 degrees higher.

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One of our hottest ever
recorded rail temperatures was

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62 degrees.

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If we stressed our
rails for exceptionally hot weather,

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they wouldn't be safe for
the winter and we'd have broken

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rails because it's too cold.

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That's why other
countries choose different temperature

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ranges depending
on their climate.