Mystery Blob revealed as emergency exit structure in Helsinki

Today, the identity of an unidentified structure discovered during excavation work in Helsinki has been revealed. Dubbed the “Mystery Blob,” this concrete structure serves as an emergency exit route for the civil defense shelter located in the adjacent Elanto building. Access to the structure is through a low corridor leading from the building’s basement. A metal hatch located two meters underground is affixed to the side of the structure, which is also covered by street asphalt.

The emergency exit route is designed to be utilized in case the building collapses on top of the shelter, blocking normal exit pathways. A pertinent question arises regarding how an underground exit can be accessed in such emergencies. Jari Markkanen, a civil defense planner with Helsinki’s rescue services, notes that it is common practice to unearth emergency exit routes for shelters.

Markkanen cites an example from Helsinki’s Kallio district, where a trial activation of a shelter revealed an emergency exit hidden one and a half meters under the courtyard’s grass. In scenarios where authorities mandate the use of civil defense shelters in Finland, all emergency exits must be unearthed, which can include clearing areas beneath asphalted parking lots—often requiring a crowbar or an excavator.

Emergency exit routes for residential buildings are typically positioned far enough from the building to avoid obstruction in the event of a collapse. According to Markkanen, the safe distance is calculated as one-third of the building’s height. By law, civil defense shelters must be usable within 72 hours when their activation is ordered, while normal conditions may see personal belongings stored inside. The locations of emergency exit routes are documented in evacuation plans, required for residential buildings with at least three units, and are subject to inspections by rescue services for readiness.