HVAC Psychrometric Chart Practice Questions Fire Protection Sprinkler System - DHQC

Fire Protection Sprinkler System

Defence Headquarters Complex - Block 6

Project Overview

The Defence Headquarters Complex (DHQC) is one of the largest construction projects in Sri Lanka with an initial estimated cost of LKR 58 billion. Block 6 is a 10-story building to be used for administrative offices of the Sri Lanka Army, requiring a comprehensive fire protection sprinkler system designed to international standards.

Key System Characteristics

System Design Details

Risk Analysis

The building was classified as high-risk due to its height (56.5m) and contains office areas with medium fire load (wooden/plastic furniture, papers). With sprinkler protection, the risk profile improves to A1.

Sprinkler Specifications

  • Concealed pendant type in occupied areas
  • Upright type in ceiling voids
  • K-factor: 80 (±4)
  • Temperature rating: 68°C (red bulb)
  • Quick response thermal sensitivity

Monitoring & Control

The system includes comprehensive monitoring with supervisory switches on all valves and flow switches for each zone, connected to the Fire Alarm Control Panel (FACP) for immediate alerting of any system changes or activations.

Design Parameters

Parameter Value Reference Standard
Maximum spacing between sprinklers 4m × 4m BS EN 12845:2004
Maximum area coverage per sprinkler 12 m² BS EN 12845:2004
Assumed Maximum Area of Operation (AMAO) 216 m² BS EN 12845:2004
Minimum sprinkler discharge pressure 0.35 bar BS EN 12845:2004

Protected Area by Floor

Floor Level Protected Area (m²)
Lower Level 3 (LL3) 5,338
Lower Level 2 (LL2) 6,411
Lower Level 1 (LL1) 6,411
Ground Floor 3,446
First Floor 3,446
Second Floor 3,400
Third Floor 3,404
Fourth Floor 3,407
Fifth Floor 3,326
Sixth Floor 3,009
Total 41,598

Key Design Standards