How Are Winter Tires Tested to Earn the Mountain Snowflake Symbol?

Every year, hundreds of winter tires are tested to see if they can pass the snow traction tests that will earn them the severe service mountain snowflake symbol. It’s an intricate test: Engineers need just the right air temperature, just the right type of snow, and special instrumentation for measuring snow traction performance.

 

In the 1990’s, the U.S. Rubber Manufacturers Association and the Tire and Rubber Association of Canada were looking for a way to help drivers identify tires that were designed to perform in severe snow and cold weather conditions. In 1999, they came up with a snow traction test that winter tires must pass in order to receive what we now know as the severe service emblem—the snowflake on the mountain peak.

 

Now drivers searching for winter tires or all-weather tires look for that winter tire symbol. So, what’s really involved in the testing that leads to tires earning that emblem?

 

To find out, we spoke to one of the engineers at Smithers Rapra, which operates an outdoor winter tire testing facility in Michigan, not far from Sault Ste. Marie, Ontario.

 

The conditions

 

To simulate the kinds of winter conditions where these winter tires will be used, the testing team checks several things before testing can be carried out:

 

  • The ambient (air) temperature must be less than 3 C. The rubber compound of summer and all-season tires hardens at 7 C. Winter tires contain a special rubber compound that keeps them soft and flexible in extreme cold.

 

  • The snow temperature must be between –15C and –3C.

 

  • The snow has to be medium pack snow. Smithers uses natural snow that falls at their site during their December to April testing season. Medium pack snow—neither hard-packed nearing icy, nor too soft and powdery—really puts winter tires to the test for snow traction because the tread can bite into it. If need be, the test team uses their specialized snow preparation tools to move snow around and break it up to create the perfect medium pack snow.

 

The test

 

Winter tire testing standards are defined by the American Society for Testing and Materials (ASTM). Tire manufacturers can conduct these tests themselves, or hire a private testing company such as Smithers to do it for them. Manufacturers use the results from these tests to determine whether they can brand their tires with the mountain snowflake symbol.

 

ASTM standard F1805 specifies what kind of vehicle can be used to carry out the snow traction tests, and standard E1136 specifies which kind of specially built test tire is used as the control for these tests.

 

Here’s how the rest of the test works:

 

  • The test tires must be stored outdoors in a shaded area so they come to the test area cold, and the test tire goes on the right rear tire. The left rear tire, which is not being tested, has a traction chain on.

 

  • The test vehicle uses special instrumentation to measure two forces—the vertical force (how much weight is pressing the tires into the ground), and the longitudinal force (the force that causes the vehicle to accelerate). The longitudinal force is divided by the vertical force to get what’s called the ‘traction force coefficient.’

 

For example, if a tire has 1,000 pounds of vertical force and it generates an acceleration force of 500 pounds, its force coefficient 0.5. The higher that number is, the better. To meet ASTM winter tire standards, the test tire has to reach 110 per cent of the control tire’s coefficient. If the control tire has a coefficient of 0.25 and the test tire has a coefficient of 0.5, then it’s at 200 per cent of the control and exceeds requirements to be designated for severe service.

 

  • The test is executed: The vehicle drives at a speed of 8 km/hr and the driver applies the brakes to three of the vehicle’s wheels to keep the vehicle speed constant while a control system causes the test wheel to accelerate from 8 km/hour up to 32 km/hour and spin out. This simulates what it might be like getting out of your driveway on a snowy morning.

 

While the tire is spinning out, its forces are measured and then these are compared with those measured for the control tire. The test is repeated over three different days and the tire manufacturer receives the average result.

 

 

This is why it’s always best to outfit your vehicle with quality winter tires or all-weather tires to ensure you’re going to get the performance you need in winter conditions.

 

When you’re looking for superior safety, be sure to look for winters that bear the severe service mountain snowflake winter tire symbol so you’ll get proper traction at temperatures between 7 C and freezing extremes.

 

The severe service mountain snowflake symbol is an easy way for drivers to identify designated winter tires and all-weather tires.

The severe service mountain snowflake symbol is an easy way for drivers to identify designated winter tires and all-weather tires.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Source of winter tires testing process: Smithers Rapra.

Do You Need Winter Tires or All-Weather Tires?

In Canada, there are two types of drivers when it comes to tires: the kind who switch out their summer tires for dedicated winter tires, and those who can run one set of all-weather tires year- round.

If you need new tires this fall, figuring out which kind of driver you are will help you spend your tire budget wisely and enjoy optimum safety in the sleet and snow ahead.

 

Driver Type #1 – Drivers Who Need Winter Tires

 

Where you live – Cities, suburbs or rural areas with heavy snow and consistent winter conditions

 

Where you drive – Highway, mountains, unplowed roads

 

Conditions you face – Harsh winters filled with heavy, hard-packed snow, ice and moderate to extreme cold

 

Why you need winter tiresWinter tires feature an aggressive tread pattern with deep, chunky tread blocks that bite ice and snow and then push them away for superior traction. You’ll also get necessary braking and cornering control on ice and hard-packed snow because winter tires are made with a rubber compound designed to stay soft and flexible even at – 30 C.

 

If you face a lot of rough, wet and black ice, you might also want to consider studdable winter tires. Metal studs give you optimum grip on ice and freezing water.

 

Driver Type #2 – Drivers Who Need All-weather Tires

Where you live – Urban centres, suburbs

 

Where you drive – City, highways

 

Conditions you face – Milder winter conditions with heavy rain, light snow and slush.

 

Why you need all-weather tires – Unlike all-season tires, all-weather tires bear the mountain snowflake designated winter tire symbol so you know they’ve passed requirements for safe driving through winter in Canada.

 

That’s because all-weather tires use a unique rubber compound that keeps them soft at temperatures above and below 7 C (the point at which all-season tires get cold, hard and slippery). They have a great slush evacuation system to prevent hydroplaning and slushplaning, which is both dangerous and common in areas with milder winters. All-weather tires also have thick tread blocks for biting grip on snow and slush when you’re heading up to the ski hill.

 

All-weather tires do a great job of doubling as superior summer tires, offering the same sensitive handling on wet roads and bare asphalt.

 

City drivers love all-weathers because they get the winter safety and performance they need without the hassle or expense of buying and storing a second set of tires.

 

To find the best all-weather tires Canada has to offer and find the one that suits your budget and needs, check out our infographic Kal Tire’s Lineup of All-Weather Tires.

Photo Credit: istock/Thinkstock.com

Looking for Reliable, Studdable, Affordable Winter Tires? Meet the Nordman 5

The Nordman 5 is quickly becoming one of Canada’s best winter tires because it ticks every box: studdable, reliable, durable, and even affordable. With a budget-friendly price point and the latest safety features, this is a winter tire that’s tough to beat.

Here in Canada, drivers face extreme cold, blistery storms and a lot of slush through the winter months.

These are just some of the features that make the Nordman 5 one of our most popular value-priced premium winter tires:

 

Advanced stud grip for excellent braking

The Nordman 5 is a studdable winter tire. Studs give you excellent winter grip in conditions with wet and black ice and hard-packed snow.

 

Winter-long stability

In slush, the second-most dangerous driving condition, you’ll still see precise handling because of how the slush grooves on this directional tread pattern expel slush and remain stable on all winter surfaces.

 

Reinforced steel belts under the tread and wide tread blocks prevent tread squirm to keep your tires stable on dry or snow-covered roads.

 

Environmentally friendly design

The Nordman 5 is made with purified, low aromatic oils. You’ll see a little leaf symbol on the sidewall that indicates this is one of their ‘green’ winter tires.

 

Value

To give drivers a more affordable studdable winter tire that stands up against Canada’s winter tires, the Nordman 5 is manufactured at the height of efficiency to reduce production costs.

 

Safety indicators

With the Nordman 5, you’ll always know when it’s time to buy new winter tires. The Nordman 5’s Driving Safety Indicator (DSI) uses numbers on the centre rib of the tread make it easy to quickly see your remaining tread depth. The Winter Safety Indicator (WSI), a winter snowflake symbol visible to a groove depth of four millimetres, reminds you when it’s time for new winter tires to ensure your safety.

 

Have you driven an earlier generation of Nordman winter tires? How did you find their performance?

Photo Credit: Gudella/istock/Thinkstock

How Can You Get Your Vehicle Ready for Winter?

Over the next six months or more, old man winter’s going to put your vehicle to the test with snow, sleet, ice and sub-zero temperatures. How can you get your vehicle ready for winter so you’re not left in a snow drift or stuck with a dead battery?

 

Prepare your vehicle to handle the rigours of winter with these simple maintenance tips:

 

1) Check your battery

When your car battery is in good shape, you’re set: your vehicle has a better shot at starting despite freezing temperatures.

 

Canada’s cold temperatures actually preserve the life of car batteries by resisting internal corrosion, and batteries in good shape can actually handle severe cold pretty well.

 

A fully charged lead-acid battery can survive 40 to 50 degrees below freezing, but a battery with a low state of charge can freeze at temperatures as high as -1 C.

 

If your battery’s been acting up and it’s only fall, read our post How to Tell if Your Battery is Dead or stop in at a Kal Tire store for a free battery test.

 

2) Get your winter tires on

Not sure when you should put on your winter tires? Remember this rule: When the temperate is 7 C at best, you need your winter tires or all-weather tires with a severe service symbol.

 

While winter tires have more aggressive tread designs to grip ice and snow and expel slush, they also have a different rubber compound that allows them to remain soft and sticky at near and sub-zero temperatures. That’s really the biggest difference between all-season, all-weather and winter tires: the rubber compound.

 

Engineers have figured out that the rubber compound that gives all-season tires their long tread life turns hard and loses traction (think of a slippery hockey puck) at about 7 C.

 

Don’t forget to save your sleek custom wheels for your summer tires and use your original equipment steel wheels for winter. Steel wheels are better able to withstand salt, gravel and potholes.

 

3) Get a winter oil service

While your vehicle is in the shop getting winter tires installed, have a winter oil service done so we can check to make sure all your fluids and components are healthy. As part of our True Service Inspection, we’ll check everything under your hood, from brakes and fluids to tires and transmission fluid.

 

4) Install winter wiper blades

Winter wiper blades feature anti-clogging armour that blocks ice from freezing around the joints, a sturdier frame and a robust rubber blade designed to stay soft in freezing temperatures, all so you can see the road in even the most blistery conditions.

 

5) Pack a winter emergency kit

Since you just never know when a storm could hit or a deer could send your car into the ditch on the way to the ski hill, be prepared to stay safe and warm with a winter emergency kit.

 

An emergency kit should include a first aid kit, bottled water, health bars, boots, gloves, and an extra winter coat and boots. Make sure you’ve also got some emergency supplies for your vehicle, including booster cables, extra oil and windshield washer fluid, lock de-icer, flashlight, flares or safety triangles, an ice scraper, a shovel, a bag of salt or gravel, and possibly even some chains for your tires.

 

What else do you do to get your vehicle ready for winter driving?

Catch of the Season: Free Salmon with Your Winter Tires

What do sockeye salmon and winter tires have in common? Turns out they’ll go together for nearly 4,000 Lower Mainland drivers this fall as part of Kal Tire’s Free BC Sockeye promotion

 

“Some of our senior managers were out salmon fishing over the summer, and they came up with the idea of teaming up with local fishers and butchers to promote this wonderful resource we have,” says Greg Waring, Kal Tire’s VP of marketing.

 

At 24 Kal Tire locations across the Lower Mainland, the first 3,600 customers who purchase a set of personal use passenger or light truck tires beginning Sept. 22 will receive a cedar salmon plank and a coupon to pick up a full fresh-caught sockeye salmon, already filleted and flash frozen, at any Meridian Meats & Seafood location.

 

All of the wild salmon, an Ocean Wise-recommended species, will be caught in the Johnstone Strait near Campbell River, BC, by young First Nations fisher Josh Duncan and his crew.

 

“Opportunities like this with Kal helps pave the way for other fishermen and hopefully other companies who want to support the wild salmon industry,” says Duncan, who heads R.A. Roberts Fishing Ltd. He also sits on the board of directors for the BC Salmon Marketing Council, committed to sustaining one of BC’s top resources by harvesting it with tradition, skill, care and pride.

 

Along with his crew, Duncan, who began salmon fishing in the Johnstone Strait as a boy, will fish the strait in a 93-foot fishing vessel named Western King, turning 50 years old this year and owned by hereditary chief Tony Roberts Sr. With each sockeye weighing about five pounds, Western King will haul approximately 20,000 pounds of salmon to shore for the ‘Free BC Sockeye’ promotion.

 

“It’s a pretty cool and interesting way to get more of our product out there locally,” says Duncan, who made headlines in August when he dropped off 500 sockeye to the homeless and others lobbying for affordable housing in Vancouver’s Downtown Eastside. This year, there is plenty to go around: 2014 has been projected to be the year of the biggest sockeye salmon run in BC history as the nearly 72 million progeny of the epic 2010 salmon run migrate through the province.

 

The wild salmon caught by Duncan’s team for Free BC Sockeye will be filleted and flash frozen by Grande Hale Seafood, distributed by Meridian Meats and Seafood, and served on cedar planks from Valleywood Remanufacturing in Lumby, near Kal Tire’s Vernon office.

 

“Everyone gets excited about a good salmon run, and we’re really glad to partner with local butchers, local businesses and a local fisherman like Josh who believes in giving back,” says Waring. “This way we can work together to promote a vital BC resource and celebrate a successful season.”

 

If you love salmon and you need new winter tires this year, beat the winter tire rush and enjoy optimum safety. Summer and all-season tires become hard at 7 C. Either choose winter tires, or, for superior year-round performance, choose all-weather tires whichremain flexible at temperatures above and below 7 C.