Why are hot vehicles dangerous for kids?

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One death is too many

Every year, children die from paediatric vehicular heatstroke across North America because they are left alone in a hot vehicle. Based on US data (noheatstroke.org), most paediatric vehicular heatstroke cases happen in children 3 and under

  • More than 50% of these deaths happen because parents/caregivers forget a child in the car
  • About 20% of deaths occur when children are intentionally left in a vehicle
  • Around 25% of deaths happen after a child gains access to a vehicle and becomes trapped. In these cases, most children are 2 to 4 years old

No one thinks it could happen to them

  • Most cases of children dying in hot vehicles occur because a parent or a caregiver forgets a child in a vehicle 
  • “Forgotten baby syndrome” is one of the key reasons why children die in hot cars
  • Key factors that contribute to forgotten baby syndrome include:
    • a change in the driving route
    • a change in how you interact with the child during a trip (for example, young children, especially babies, often fall asleep in their car seat and the driver may no longer remember they are there because they are so quiet)
    • attention or memory lapses due to distraction, stress, or fatigue

Vehicles warm up quickly

The air inside a vehicle heats up quickly due to the “greenhouse effect”. This means that when the sun strikes objects inside a vehicle – like the dashboard, steering wheel, or a seat – it slowly heats up those objects. Those objects then warm the air inside the vehicle.

Even vehicles which were recently air conditioned can heat up to unsafe levels. The temperature inside a previously air-conditioned vehicle can jump to over 50⁰C within 20 minutes on a 20⁰C day.

Although vehicles heat up more regularly in summer months due to higher exterior temperatures, inside car temperatures can still rise to unsafe levels on cooler days. Therefore, it is never safe to leave children alone in a vehicle.

Children are more susceptible to getting heatstroke

Heatstroke happens when a child's body temperature rises beyond a safe range.

A child's body can overheat quickly, about 3 to 5 times faster than an adult's. This is because their bodies are less efficient at regulating their temperatures. When a child has heatstroke, their body creates more heat than it can release which can lead to brain damage or death.

Infants and young children are at higher risk of harm in extreme heat because they rely on caregivers to recognize symptoms, open car doors, unbuckle them, or remove layers of clothing.

When a child is left in a hot vehicle, their temperature can continue to rise. This can lead to heat exhaustion and symptoms like:

  • intense thirst
  • weakness
  • discomfort
  • anxiety
  • dizziness
  • fainting, and
  • headache

If the child isn't removed from the hot vehicle, this can lead to heatstroke.

Heatstroke is the most serious type of heat illness. Symptoms of heatstroke include:

  • a core body temperature higher than 40⁰C
  • rapid, shallow breathing
  • complete or partial loss of consciousness
  • reduced mental ability
  • delirium
  • seizures, and
  • death

There's no safe way to leave a child alone in a vehicle

  • Leaving windows slightly opened in a vehicle may not be enough to improve air circulation. The vehicle can still heat up quickly and the windows may not reduce the temperature
  • Leaving a child alone in a car is unsafe, even if you leave the air conditioning running. Your vehicle is at risk of being stolen because the ignition is on, and the doors could be unlocked. Children can accidentally operate power windows, lock the vehicle, and become trapped
  • Police take these incidents seriously. You could be charged if you leave a child alone in a vehicle. Make sure you understand the rules for your province or territory regarding leaving a child unattended

You should never leave a child alone in a vehicle, whether it's hot or not. The risk of injury or death is too high.

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