Report a SIS

Technical Notes for Responding Rescuers


SIS victims have been recovered by their partners in as little time as 20 minutes without success. By the time Ski Patrol or SAR personnel are involved the average time of recovery is 15 hrs.

That said there have now been documented cases where professional rescue personnel have been able to respond and successfully extricate potential victims. Cell phone calls from witnesses and in some cases the victim themselves have been one key factor in this success. Rescue groups with a well-published local emergency number may have a greater chance of immediate notification directly from the accident site. Rescue groups can also be good providers of education on SIS awareness and prevention.

If a reported incident is directly witnessed:

Take the witness to the point last seen if conditions allow,
Don’t wait for the witness, but bring the witness to the site as soon as possible. Continue to conduct the witness interview en route to the site and pass the information via radio or cell phone to the initial response team.
Check scene safety and,
Begin a hasty search of the location as per your Patrol protocol.
It is important to note that from 2001- 2011, 87% of the reported SIS victims have had some part of their body or equipment exposed. Therefore a rapid visual course search of the area is the best chance for success. Following ski tracks in the area is very helpful but this opportunity can be extremely short lived during storm conditions.
If your group has Avalanche Dogs they should be sent as soon as possible.
Probing of individual tree wells can be used if there is a high degree of certainty of the last seen area.
Other equipment based rescue techniques like a Beacon Search or RECCO Search may be useful but have had limited success to date.
Continue to work with additional resources as is necessary or as conditions warrant.
If a person is located in deep snow or in a tree well IMMEDIATELY begin snow immersion rescue efforts discussed above.

If reported as a possible “Missing Person”

Unless directly witnessed, a Tree Well or Deep Snow Immersion incident may most likely be reported as a Missing Person, therefore, these three steps are helpful in responding to such reports:
Initial Thorough Interview of Reporting Party –

  1. What is the possibility the Missing Person was skiing or riding in a deep snow or tree well area and get the usual identifying information.
  2. Are they wearing a transceiver or Recco device, etc.
  3. Are conditions conducive to SIS hazards?

In addition to being aware of current snow conditions, it is useful to poke around tree well bases and deep snow areas to help evaluate the depth and density of snow. This information can help give you an idea of what the current local risk factor for a SIS event is and can help you identify the appropriate level of urgency to respond to a missing person report.

If conditions appear to be conducive to SIS hazard: Quick Response – Hasty Search as per your Patrol protocol of Point Last Seen and expand search as evidence and information may become available.

If a person is located in a deep snow or tree well immersion situation, IMMEDIATELY begin snow immersion rescue efforts as described above.

If you are aware of a SIS accident lease fill out and send in a Snow Suffocation Accident Report as soon as possible as this will help with continuing research. The form can be found on line at