Effective Shovelling

The information in this article is a précis of a great article Strategic Shovelling by Edgerley and Atkins. It's well worth a read in it's entirety, if you have the time. Here are it's main points.

All avalanche rescues involve shovelling while only a fraction require multiple burial searches techniques, so we should be concentrating our energies on Shovelling. One of the most reported issues of any rescue was the time and effort required to extract the victim from the snow. Advances in transceiver technology have given us easier to use transceivers which has led to a drop in victim location times, to the point where location is now a relatively short phase of the whole rescue. We must improve the exraction times.

Althought the majority of this research was conducted by BCA, they are not doing it to sell anything, it doesn't matter what shovel you have (although any metal blade is better than a plastic blade), it's just good helpful information.

There are 2 main digging methods, Cone & Terrace

Cone technique is basically the default method. After pin pointing your victim with a probe, you dig down and around the probe untill you locate the victim. You then dig towards the head to establish an airway and then finally fully extract the victim.
Terrace shovelling is a more planned approach where the digger estimates the depth of the victim using their probe and then starts digging 1.5 times the estimated depth downhill of the probe and digs inwards rather than down.

While the Cone method allows the minimum removal of snow to reach the victim, there are several major drawbacks. These are;

1. Trampling of the victims airway. The rescurer is compressing the snow around the victim possibly standing right on their head and increasing the chance of suffocation.
2. Increasing the stress of the victim. Many victims have reported how frightening it was to have someone jumping up and down above them. Increased stedd leads to increased oxygen use.
3.Deep burials lead to the narrow cone restricting the movement and speed of the digger and problems of snow removal and snow falling back in the hole.
4. Once the victim has been reached, a lot of snow may need to be moved to clear the airway and the cone is not a good shape for this. Research has found that quite often the victim needs to be rolled to establish a clear airway and this is very difficult using the cone shape.

A much better method is the Terrace Dig. By digging an arms width terrace downhill of the victim and approaching from the side, all of the above problems are removed. Whilst more snow has to be moved to initially reach the victim, it has been shown that all that snow will have to be removed anyway to establish an airway, so there is no difference. The Terrace method also has the following advantages

1.It is much easier for 2 diggers to work together side by side ( the most effcient) or one at the face and one clearing snow as the terrace becomes deeper.
2.The digger can work on their knees or sitting down which is more ergonomic and quicker than standing.
3.Initially snow can be thrown out of the hole sideways until the hole is waist deep, after which the snow is thrown out the back. Since the snow is moving downhill, gravity is not having to be overcome to remove the snow.
4.If the victim needs to be rolled the hole shape is much better suited to this.
5. If the burial is really deep and you have the manpower it allows a much more effcient team to be organised. See diagram below.

Effective shovelling technique has the potential to reduce rescue times dramatically and at no extra cost. Another element, along with transceiver technique, that is worth practising before you have to do it for real.