Avaluator - how to use it?
The Avaluator Card and its accompanying booklet show you how to make critical decisions before and during your adventures in the backcountry. (To read more about what the Avaluator is and how it was developed see the article: Avaluator - avalanche accident prevention card alive!)
The Avaluator Card and its information booklet focus on four key decisions and travel skills: trip planning, identifying avalanche terrain, slope evaluation and good travel habits. The Avaluator Card is a hand held card that can be easily carried on all your backcountry trips.
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The Avaluator Card - front side - Trip Planner
The Avaluator's front side is designed to help you when planning your trips and to serve you as a constant evaluation tool while traveling through various backcountry terrain. The Avaluator will help you to determine the level of potential avalanche danger and provides valuable feedback about how 'safe or unsafe' the given conditions are at that moment. The Avaluator sets out conditions under three headings: NORMAL CAUTION, EXTRA CAUTION or that it is NOT RECOMMENDED for you to continue your trip under the given conditions.
This is The Avaluator's front side. Study it carefully and you will be able to easily understand the following text.
The horizontal axis shows the three possible levels of terrain rating. They are based upon Parks Canada's Avalanche Terrain Exposure Scale. Terrain is rated as SIMPLE, CHALLENGING and COMPLEX. The vertical axis shows the avalanche danger rating, which is shown as LOW, MODERATE, CONSIDERABLE, HIGH and EXTREME.
Avalanche danger ratings are issued in avalanche bulletins that are produced by the Canadian Avalanche Centre. These ratings are estimated by performing snow stability tests. The following chart shows the terrain rating system that you should get familiar with in order to use the Avaluator Card properly.
| Avalanche Terrain Exposure Scale - Parks Canada |
| Terrain |
Terrain Criteria |
| SIMPLE |
Exposure to low angle or primarily forested terrain. Some forest openings may involve the runout zones of infrequent avalanches. Many options to reduce or eliminate exposure. No glacier travel. |
| CHALLENGING |
Exposure to well defined avalanche paths, starting zones or terrain traps; options exist to reduce or eliminate exposure with careful route finding. Glacier travel is straightforward but crevasse hazards may exist. |
| COMPLEX |
Exposure to multiple overlapping avalanche paths or large expanses of steep, open terrain; multiple avalanche starting zones and terrain traps below; minimal options to reduce exposure. Complicated glacier travel with extensive crevasse bands or icefalls. |
So how do you use the Avaluator's front side?
Based on the avalanche danger rating and the terrain exposure scale you can determine what actions to take:
Example 1:
If the avalanche danger according to an avalanche bulletin is HIGH and you evaluate the terrain that you want to travel in as CHALLENGING then you find yourself in the Avaluator's 'red zone', which means that it is NOT RECOMMENDED to ski or ride under such conditions. Perhaps, it is best to refrain from all backcountry activities and stick to the lifts if you really, really want to ski today.
Example 2:
A bulletin predicts the avalanche danger as MODERATE and a terrain for today's trip can be rated as SIMPLE to CHALLENGING with a few sections rated as COMPLEX. Everything looks quite safe and you are set for an awesome day of spring skiing.
After a couple of "kick ass" runs you set your eyes on a big, south facing, 35-40° slope. It is around 2pm on a sunny afternoon and you feel very confident getting it done before sunset, even with some navigation through small crevasses that are under the slope.
While all this sounds like a good plan you should be aware that the snow has likely become wet by this time of the day (in the spring) and the avalanche danger rating could have changed to CONSIDERABLE since the morning. Keep in mind that 'the big, south facing, 35-40° slope' and 'the small crevasses' make this COMPLEX terrain. A quick check of the Avaluator Card will show you that conditions have become treacherous. That means that this is a line should be visited the next day, in the early morning, rather than try to push just because you have time.
The Avaluator Card - back side - Obvious Clues
The back side of the Avaluator Card consists of seven crucial questions that will help you to recognize the obvious clues of potentially dangerous conditions. This feedback will show you whether to use NORMAL CAUTION, EXTRA CAUTION or that traveling under such conditions is NOT RECOMMENDED.
How do you use the Avaluator's back side?
The seven question's on The Avaluator Card are related to snow stability and avalanche conditions:
- Are there signs of slab avalanches activity in the area within the last 48 hours?
- Was there loading by snow, wind or rain in the area within the last 48 hours?
- Are you in an avalanche path or starting zone?
- Are there gullies, trees or cliffs that would increase the consequences of being caught?
- Is the danger rating considerable or higher?
- Are there signs of unstable snow, such as whumpfing, cracking or hollow sounds?
- Has there been recent significant melting of the snow surface by sun, rain or warm air?
When you are in doubt about any slope (whether skiing or climbing) you can use these questions to your advantage. For any question answered 'yes' give yourself one point. After answering all seven, add up all the times you answered yes. If your result is between 0-2 points use NORMAL CAUTION when approaching or skiing the slope in question. For a result between 3-4 pts use EXTRA CAUTION. If it is between 5-7 pts you should turn around and go somewhere else as you are positioning yourself for a disaster scenario.
Example 1:
Assume that you answered 'yes' for questions #3, #4 and #5, adding up to 3 points. This score shows that you are already in the 'yellow zone' as shown on the back side of the Avaluator Card. The 'yellow zone' shows you to use EXTRA CAUTION. Be aware that as you ski or climb the slope in question and you notice at least one more sign of the obvious clues you are still in the 'yellow zone' (extra caution) but you are now on the edge of the 'red zone' and the NOT RECOMMENDED travel advice.
Example 2:
Let's imagine that you are about to climb a steady, 35° slope that is 500 metres or 1500 feet high (vertical gain) and ends on a round, 5 metre wide ridge. There is 10 cm of new snow in the area.
Obviously, you notice that this is going to be a pretty tough climb because of the steepness and the new snow. But what other obvious clues do you notice? As you go over the obvious clues questions you give yourself 2 points for questions #3 and #4, resulting in NORMAL CAUTION. So you should be safe to continue this climb.
But is it really that safe? Maybe not. Since the whole slope ends with a ridge it is very likely there were/are winds blowing over it and with the new 10 cm of snow there might have occurred or is still occurring a loading by wind. If this is the case then question #2 is also 'yes' which can easily translate to 'yes' for #5 as well. It is also possible that there will be a 'yes' to #6 once you start approaching the final metres of the climb which can put you in a very treacherous situation. In this case you should use EXTRA CAUTION right from the beginning because even with your initial 2 points you are not that far from accumulating 5 points. 5 points would result in a rating of NOT RECOMMENDED to travel.
Start using the Avaluator Card
We strongly recommend that you start using the Avaluator Card and that you read its accompanying booklet even before you start using the Card itself. Of course, the Avaluator is not a miracle tool that would totally steer away any danger from your paths, but it is a great tool to teach you a consistent and statistically reliable approach in your decision making process especially in critical situations.
Visit our safety store to order the Avaluator package. At only $10 the Avaluator is worth every cent for such a valuable tool. Every purchase of an Avaluator will also show your support for Canadian Avalanche Association and its Avalanche Centre because we donate 100% of all the profits to these important institutions.
- Avaluator is a registered trade mark of the Canadian Avalanche Association.
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