*This article is a partial remake of the article published in the 2023-2024 season
What if you encounter an avalanche in the backcountry (BC) and someone gets buried?
A probe is a piece of gear that uses a beacon to detect the point where someone has been buried by an avalanche and is inserted into the snow to pinpoint the buried person's location. When folded, it is compact at 20-30cm, but when you pull the cord, the shaft joins and automatically extends to a length of 2-3m.
Probes are essential for backcountry adventures, and they come in a variety of lengths, weights, shaft materials, and ease of use. What should you look for when choosing one?
The role of the probe
A probe is a stick used to search for people buried in the snow. It is also called a sonde. By the way, probe is English and sonde is German.
It is considered essential avalanche gear, along with a beacon and a shovel, when skiing with a backcountry.
After the beacon has determined the approximate location of the buried person, a probe is thrust into the snow to more precisely pinpoint the rescuer's location.
The beacon can roughly locate the buried person's location, but it still doesn't tell rescuers where to dig in the vast snow surface to find the buried person. Ultimately, the rescuer finds the buried person by feel with the probe.
The probe also has a scale that is used not only for avalanche searches, but also for "pit checks" to check the snow depth and snow layers to see if the area you're about to ski is prone to avalanches
How the probe works
The probe is made up of cylindrical rods about 40 to 50 cm long connected by wires running through the inside, which can be quickly assembled into a single long rod when in use. The rod parts are called shafts, and the longer the rods, the more shafts there will be
The length varies depending on the application and environment, from just under 2m to over 3m. When not in use, it can be folded up and stored compactly
Tips for choosing
The key points to consider when choosing a probe are the length and thickness, the material, the assembly method, and how easy it is to read the scale
■ Length + Thickness
Naturally, if the pole is too short, it will be difficult to conduct a proper search. If the burial depth during an avalanche is less than 2m, there is a good chance of rescue with prompt rescue efforts, so a pole of at least 2m in length is desirable. Incidentally, the poles used by mountain guides and mountain rescue teams are around 3m long, but for general BC users searching for group members, it is not necessary to use poles as long as professional poles.
Regarding thickness, if the pole's diameter is too small and thin, it will not be strong enough and will have difficulty penetrating hard snow. It can also bend easily. Longer poles are often thicker, and thicker poles are less likely to bend or break, so a pole with a certain thickness is best. Also, if the length of a single pole to the shaft is too long, the joint will tend to be unstable. Be sure to check the connection parts as well.
There is a certain degree of correlation between length and price. Considering that balance, it is easy to find a length between 230cm and 280cm. Also, in terms of storage, a foldable sled that is about 50cm long when folded will fit easily in a backpack
■Material
The materials used for probes are most often aluminum or carbon. Carbon is expensive but very light. However, it is more likely to break than aluminum when a certain amount of force is applied. At the same time, aluminum is strong and not easily broken, but it also has the characteristic of being easily bent. If you are looking for lightness, carbon is the choice, but aluminum is the choice for cost performance
■ Other elements
Other things to consider when choosing a probe include the ease of reading the scale and the assembly method. Many probes assemble automatically and quickly by pulling the handle. Some probes are also equipped with the latest technology, such as unique probes that receive beacon signals at the tip of the probe, determine the location of the buried subject, and notify you of a hit with sound and light
How to use the probe
Now that you understand what a probe is, let's take a look at how it's actually used on snow.
(Video: Japan Avalanche Search and Rescue Council)
Unless you practice using beacons and probes on the snow, it will be difficult to use them quickly and accurately when you actually encounter an avalanche and are forced to use them. Beginners to backcountry skiing should start by taking a course on how to use avalanche gear or joining a tour led by a backcountry guide that includes training, so that they can become familiar with how to use the equipment