*This article is a partial remake of what was published in the 2023-24 season.
What if someone gets buried in an avalanche in the backcountry (BC)...
A probe is a piece of gear that uses a beacon to detect the burial point caused by an avalanche and pinpoints the location of the buried person by inserting it into the snow. When folded, it is compact at 20 to 30 cm, but when you pull the cord, the shaft joints and automatically lengthens to 2 to 3 meters.
Probes are essential for going out into the backcountry, and there are many different types of probes, including length, weight, shaft material, and ease of use. What points should I focus on when choosing?
The role of probes
A probe is a stick used to search for people buried in the snow. Also called a sonde. By the way, the probe is in English and the sonde is in German.
Along with a beacon and shovel, it is considered essential avalanche gear for skiing in BC.
After locating the buried person using a beacon, a probe is inserted into the snow to more precisely locate the person being rescued.
Beacons can roughly locate the location of a buried person, but it is still difficult to know where in the vast snow surface to dig to reach the buried person. In the end, you will be able to detect it using the tactile sensation of the probe.
Also, the probe has a scale. In addition to searching for an avalanche, it is also used for pit checks to check the depth and layer of snow to determine if the field you are going to ski is prone to an avalanche.
How probes work
The probe can be quickly assembled into a single long stick by connecting 40 to 50 cm long cylindrical sticks with wires running inside. The rod part is called a shaft, and the longer it is, the more shafts there are.
The length varies depending on the purpose and environment, ranging from just under 2m to over 3m. When not in use, it can be folded and stored compactly.
How to choose
The key points to consider when selecting a probe are its length and thickness, the material it is made from, the way it is assembled, and the ease of reading the scale.
■ Length + Thickness
Naturally, if the time is too short, sufficient search activity cannot be carried out.
If the burial depth in the event of an avalanche is 2m or less, there is a good chance that it can be rescued if a quick rescue is performed, so we want the length to be at least 2m or more. By the way, the ones used by mountain guides and mountain rescue teams are around 3m long, but if you're a general BC user and want to search for group members, you probably don't need to be as long as the professional ones. As for the thickness, if the diameter of the stick is too small and too thin, the strength will be insufficient and it will be difficult to penetrate hard snow. It can bend easily. In many cases, the longer one has a thicker diameter, and since a thicker one is less likely to bend or break, a certain thickness is better. Also, if one length to the shaft is too long, the joint tends to be unstable. I would also like to check the connection part.
Length and price are proportional to some extent. Considering the balance, it is easy to get around 230cm to 280cm. Also, in terms of storability, a bag with a length of about 50 cm when folded and shortened fits well in a backpack.
■ Material
The materials used for probes are very often aluminum or carbon. Carbon is more expensive, but it is considerably lighter. However, it is more likely to break than aluminum when a certain amount of force is applied to it. At the same time, aluminum has high strength and is difficult to break, but it also has the advantage of bending easily. If you are looking for lightness, then carbon is your choice, and for cost performance, aluminum is your choice.
■ Other elements
Other points to consider when choosing are the ease of reading the scale and the method of assembly. Many of them automatically and quickly assemble when the handle is pulled. There are also unique probes equipped with the latest technology that receive beacon signals at the tip of the probe, determine the position of the buried subject, and notify them of a hit with sound and light.
How to use the probe
Now that you know what a probe is, let's see how it actually works on snow.
(Video: Japan Avalanche Search and Rescue Council)
If you don't practice using the beacons and probes on the snow, you won't be able to use them quickly and accurately in the event of an avalanche. If you are new to backcountry skiing, it would be a good idea to get used to using the equipment by first taking a class on how to use avalanche gear or joining a tour with a backcountry guide with a class.