Reconsidering rescuer safety is an ongoing task. The primary safety concern is a secondary avalanche that affects rescuers.
Snow that remains above the avalanche's crown is called "hangfire." A secondary avalanche that is caused by hangfire is rarely a concern unless the snow is disturbed (e.g., somebody skis onto it) or it receives additional loading (e.g., from snowfall or wind transport).
Another possible cause of a secondary avalanche occurs when multiple avalanche paths converge above the rescuers. In this case, it is likely that the additional paths have similar characteristics as the path that slid.
I have surveyed dozens of avalanche experts and have not heard of a case where rescuers were buried by a secondary avalanche while they were performing a companion rescue on the avalanche debris. I did hear of one rescue that was called off due to secondary avalanches and another rescue where skiers who were on the hangfire triggered a secondary avalanche and were injured. There are several cases of avalanches burying professional rescuers later (often in the following days) as the snow continued to accumulate.
Most importantly, consider the significant risk to rescuers as they attempt to access the avalanche site and when they are returning to the frontcountry.
