Shelter ventilation: what the Ukrainian DBN means for project scope

Mechanical ventilation is part of the project basis

The referenced DBN provision requires mechanically driven ventilation for PRU and dual-purpose structures with PRU protective properties. Natural draft alone should therefore not be treated as a complete modern project solution for these scenarios.

The system has to be sized for the project population, room arrangement and intended operating mode.

Referenced minimum air-change scenarios

• main PRU / relevant dual-purpose rooms: at least 6 air changes per hour for new construction;
• capital repair or reconstruction: 4 air changes per hour for the referenced scenario;
• healthcare facilities: 10 air changes per hour for new construction;
• healthcare capital repair or reconstruction: 6 air changes per hour.

Backup ventilation is a separate design question

Where the selected solution relies only on electrically driven fans, the DBN also includes a backup-ventilation scenario calculated at not less than 3 m³ of air per person per hour using electric/manual fans.

This is why backup power, manual operation and the required ventilation mode should be resolved in the technical brief rather than added after equipment is installed.

What should be explicit in a supplier or contractor proposal

• design airflow and the population used in the calculation;
• operating modes and the applicable project basis;
• fan and filtration equipment included in scope;
• air intake and exhaust arrangement;
• backup operation if normal power is lost;
• commissioning, testing and handover documentation.