Baby, It’s Cold Out There!

Living in Canada means living in cold weather for a good part of the year, the worse months are normally: November, December, January, February, and March.  So, depending upon where you live in this gigantic country, the number of cold weather months can expand dramatically beyond the classic winter season of December 21st to March 21st.

Building outdoor radio networks can be difficult and challenging work.  Most modern radio equipment, be it for microwave, satellite, wireless, or optical fibre networks, is not normally specified for the extreme cold temperatures that we experience here.

Therefore, we have faced many projects that demanded customized harsh environment installations that need to withstand the rigors of Canadian weather.  We solve these installation problems by housing the radios inside a secondary housing, typically a NEMA-4 enclosure with a heating element to keep the equipment warm.  These enclosures are installed on poles, rooftops, and towers.  We have done similar projects with equipment inside heated pedestals that are ground mounted housings.  The added structural loading imposed by the housing weight can compound compliance to tower and supporting rooftop mount designs and require added remediation to carry the extra weight.  Getting electricity to the enclosure can be difficult to design too.  It is rarely smart to bring AC power up a tower due to lightning concerns (yes, we can see lightning in the winter too), so DC power is preferred.

Temperature

In one project in Regina, Canada, we had to contend with temperatures as cold as -40° to -56° C (Fahrenheit and Celsius cross at -40° C, so they can be thought of as being close: for example -56°C equals -68.8°F, besides everything dies after -40°C anyway regardless of the scale used ☺).  In this case, we had to place a radio inside a heated enclosure within a second heated enclosure in order to keep the radio warm.  In fact, when it was installed, it was so cold that the technician had to use a hot air blower to heat up the internal crystal oscillator, so it would start oscillating.  Once it was running (oscillating), it was all fine and stable.  But, sometimes these radios do not like to start in severe cold.  This is the specific reason for the temperature specifications on the equipment specification sheets, it is all about the oscillator and its stability, which needs to be precise, so there is no real way around this issue.  If the oscillator drifts in frequency, even by the smallest amount in say a satellite situation, then the signal drifts away from its assigned slot and interferes with other neighbouring carriers.  We call this SCPC or single channel per carrier and it is critical to keep the carriers centred on their assigned channels.  In microwave and wireless networks, we have similar issues for signal stability.

Humidity

In places like the Prairies, we need to think of humidity too.  It is so super dry at these ultra low temperatures and this dryness causes the circuit boards to dry out and arc.  Recently, while in the Prairies, we heard of two fires in equipment, likely due to this drying issue, and these devices were not overly old equipment so this is highly unusual for the equipment in question, but is seen in the best brands and products due to ultra dry environmental conditions.  One device was at an office site and staff saw smoke emanating from a telecom closet.  The other was at a remote site in a shelter.  So, humidity needs to be considered regardless of the location of the equipment.

Static Discharge

With ultra cold and super dry humidity comes intense static discharge.  So, you need to use grounding straps that the technician applies to their body with a Velcro wrist strap before they touch any equipment.  This way they are bonded to the same ground as the equipment, which helps to neutralize static discharge.

Wind

With the cold temperatures and near zero humidex, comes wind.  Wind further aggravates the cold and makes it effectively feel much colder than it really is, we call this the “wind chill factor”.  In some designs, we plan the placement of the housing to open in the lee of the wind.  Enclosure doors have been ripped off the housing by high winds and this is not just inconvenient, it is a serious safety hazard too.  Wind pressure on the larger housings exerts more physical load on towers.  This is especially the case when ice builds up on the housing further adding intense point loads to the tower.

Human Factors

With field workers needing to go out into these severe weather conditions, it is critical to provide a safe work setting.  Not only do they need proper clothing layered in a way to keep warm, but they need breaks to warm up and restore energy.  For the author, while it is super cold, ultra dry, and seriously windy in the Prairie Provinces of Canada, it feels much colder in Quebec during the winter as humidity from the St. Lawrence River penetrates whatever clothing you wear.  Once in Montreal, on a frigid February morning walking a good distance from my parked car to a client office, my beard and mustache froze solid from my breath.  When I touched my mustache, many hairs broke off and sprinkled down.  Recently, we have seen new innovations in work clothes with a battery powered coat that has heating elements in it.  These coats use the same batteries as the worker’s drills and other portable tools; very clever.

The Canadian Government gives us seven steps for cold weather safety.  They include:

1.  Listen to the weather forecast

• Check the Environment Canada weather forecast before going out in the winter.
• Listen for an extreme cold warning.  These warnings, based on local climate conditions, are issued when significant cold temperatures or wind chills are expected to occur.

2. Plan ahead

• Develop a cold weather safety plan in advance to ensure that you address safety concerns when it is very cold or when the wind chill is significant.

3. Dress warmly

• Dress in layers with a wind-resistant outer layer.
• When it is cold, wear a hat (we lose a large portion of our body heat from the head), mittens or insulated gloves and something to keep your face warm, such as a scarf, neck tube or face mask.
• Wear warm and waterproof footwear.
• When it is very cold, or when the wind chill is significant, cover as much exposed skin as possible. Your body’s extremities, such as the ears, nose, fingers and toes, lose heat the fastest.

4. Seek shelter

• When the wind chill is significant, get out of the wind and limit the time you spend outside.

5. Stay dry

• Wet clothing chills the body rapidly.
• Remove outer layers of clothing or open your coat if you are sweating.

6. Keep active

• Walking or running will help warm you by generating body heat.

7. Be aware

• Watch for signs of frostnip, frostbite and hypothermia.
• Some people are more susceptible to the cold – particularly children, the elderly and those with circulation problems.
• The use of alcohol, tobacco and certain medications will increase your susceptibility to cold.

Did I mention that we get snow too?

Lots of first rate engineers live in wonderful locations, such as California and Florida, where they do not experience the same kind of severe winter weather conditions that we have in the Great White North.  They put their sweaters on immediately at +60° F in these warm states and think that they are dying of the cold even at these comparatively moderate temperatures.  So, they really have no first-hand experience with really cold weather like we experience in other locations in North America.  Cold is not limited just to Canada.  I have been in northern USA states and wished I was somewhere else sipping hot chocolate and warming by a fire.  Alaska, North Dakota, Wisconsin, Montana, and Minnesota, all jump to mind as suffering from severe cold in the winter months. Just last week, when I walked a mere 800 metres in the -23° C temperatures from the hotel to the office in one cold city, the hair on my head froze solid like a construction worker’s hard hat.  Too funny.  I guess I should have used the hair dryer provided for free by the hotel instead of letting it self dry as I normally do.  When I got to Starbucks, I was dripping on the counter as my hair melted and I made a wet mess of the serving area.  Life in Canada, you have got to love it.

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About the Author:

Michael Martin has more than 35 years of experience in broadband networks, optical fibre, wireless and digital communications technologies. He is a Senior Executive Consultant with IBM Canada’s GTS Network Services Group. Over the past 11 years with IBM, he has worked in the GBS Global Center of Competency for Energy and Utilities and the GTS Global Center of Excellence for Energy and Utilities. He was previously a founding partner and President of MICAN Communications and before that was President of Comlink Systems Limited and Ensat Broadcast Services, Inc., both divisions of Cygnal Technologies Corporation (CYN:TSX). Martin currently serves on the Board of Directors for TeraGo Inc (TGO:TSX) and previously served on the Board of Directors for Avante Logixx Inc. (XX:TSX.V).  He served on the Board of Governors of the University of Ontario Institute of Technology (UOIT) and on the Board of Advisors of four different Colleges in Ontario as well as for 16 years on the Board of the Society of Motion Picture and Television Engineers (SMPTE), Toronto Section.  He holds three Masters level degrees, in business (MBA), communication (MA), and education (MEd). As well, he has diplomas and certifications in business, computer programming, internetworking, project management, media, photography, and communication technology.