Dangers of Frost
With the winter months closing in and temperatures gradually falling it is important to be prepared. Frost can be deceptively dangerous. It can form on roadways, often unannounced, with the potential to snarl traffic and send vehicles skidding out of control at the slightest brake tap or acceleration. Drivers and pedestrians may have trouble spotting frost since it appears either translucent or white, making it a hidden hazard. Its infamously difficult-to-forecast nature only exacerbates the problem.
Types of Frost
Frost is the solid deposition of water vapour from humid air. It normally forms on still, clear, cold nights. The cool night air causes water vapour in the air to condense and form droplets on the ground. When the temperature of the ground or surface is below 0 degrees Celsius the moisture freezes into ice crystals.
- Ground Frost forms on the ground or objects whose surfaces have a temperature below the freezing point of water. The ground can cool faster than the air and cause a ground frost without the air temperature dropping to 0 degrees Celsius. Grass will usually frost over before concrete or road surfaces, since grass cannot retain heat as efficiently.
- Air Frost occurs when the air temperature falls to or below the freezing point of water. The air temperature must be at or below the freezing point of water at least 1 metre above the ground.
- Hoar Frost is formed by the same process as dew, but when the object’s surface is below the freezing point. It can appear feathery when the object’s surface reaches the freezing point before dew begins to form on it.
- Glaze and rime are not types of frost, but are often confused as such. Rime is a rough white ice deposit that forms when supercooled water droplets of fog freeze on contact with a surface as they drift past. Glaze forms when supercooled rain comes into contact with the ground, or when non-supercooled liquid comes into contact with the ground if the ground is well below 0 degrees Celsius. Glaze is clear ice that can be easily mistaken for a wet surface. It is highly dangerous.
Protect Your Property
Frost does not confine itself to the roadways, it can quickly form on your property, damaging your buildings exterior, pipes and boiler. Frost can freeze and burst your pipes, causing a lengthy and messy clean-up process. Protect your property by heeding these general precautions:
- Service your boiler and insulate your pipes. Because frost can burst pipes, make sure your boiler is working properly and your pipes are insulated against the cold. If your pipes burst, you could be without heating and hot water. Stay up to date on boiler maintenance and pipe insulation to ensure your building stays warm.
- Locate your main stopcock and learn how to turn it on and off. Without knowing where and how to operate the main valve regulating water flow into your building, you may be unable to clear your pipes and thus prevent them from freezing.
- Inspect all insulation. All pipes and tanks in loft spaces or anywhere liable to freeze should be inspected and insulated properly.
- Clear all gutters. When your gutters are blocked, water overflows and runs down your outside wall. That excess water and any frost that forms on your building’s exterior can work their way through tiny cracks in porous brick and cause serious damage. Clear your gutters to prevent overflow and any damage.
- Allow heat to circulate. Heat should circulate through your whole building to ensure colder areas that contain pipes do not freeze. Keep inside doors open to encourage heat circulation.
- Survey your roof. Your roof should be watertight with no cracked or missing tiles. Even the smallest hole can provide frost with an opportunity to enter and wrench apart tiles by freezing and refreezing.
Follow us on Twitter: @
The content of this document is of general interest only and not intended to apply to specific circumstances. It does not purport to be a comprehensive analysis of all matters relevant to its subject matter. It does not address all potential compliance issues with UK, EU or any other regulations. The content should not, therefore, be regarded as constituting legal advice and not be relied upon as such. It should not be used, adopted or modified without competent legal advice or legal opinion. In relation to any particular problem which they may have, readers are advised to seek specific advice. Contains public sector information published by the Met Office and licensed under the Open Government Licence v1.0.
Design © 2014 Zywave, Inc. All rights reserved.