From: Rabbi Moshe Sofer
To: Rabbi Chaim
The Chasam Sofer rules that R' Elazar, as gabbai of the Chevra Kadisha, is exempt from all liability for pledges destroyed when a stone vault unexpectedly cracked during a Yom Kippur fire. Although members of the Chevra may have mutual shomer sachar status as partners, the heightened duty of netirusa yesirta — sacrificing one's own property to save a deposit — applies only to a guardian receiving explicit wages, not one deemed a shomer sachar through indirect partnership benefit. R' Elazar acted reasonably by saving property from a more vulnerable wooden structure while leaving the presumed-fireproof stone vault sealed.
Source: Shu"t Chasam Sofer CM §16