Smoke Detection in Places of Worship

By Consulting Specifying Engineer Staff December 21, 2004

Places of worship are among the most precious historic landmarks in the United States. Protecting these facilities and their irreplaceable contents from fire and smoke damage is of great concern to congregations and those interested in heritage preservation. After arson, the leading cause of church fires is electrical problems, which often remain undetected until substantial damage is done.

Church structures present unique problems for smoke and fire detection. Height and volume configurations, multiple entry points, airflow, obstructions, and evacuation requirements must all be considered when choosing and designing a smoke detection system. Pews and high ceilings can impede access and maintenance of traditional smoke detectors. High ceilings also require additional detectors. Airflow, smoke dilution, and smoke stratification can reduce the response rate of traditional detectors. Structural movement caused by external climatic change can cause false alarms, and the number of point or beam detectors required for large churches can be costly.

Traditional smoke detectors are not well suited to churches. They often do not detect a fire until after the incipient stage, when active flaming occurs. The structure can be damaged by both fire and smoke, and if water must be used to extinguish the fire, there will be further destruction. These systems can also be unsightly, and installation can harm internal decor.

St. Stephens Lutheran Church, in Wausau, Wisconsin, highlights the challenges of smoke detection in houses of worship. An example of High Victorian Gothic architecture with craftsmanship nearly 100 years old, the value of this historic landmark is estimated at $7 million. Its assets include many irreplaceable items, including a century old hand-carved altar and a bible that was a gift from Emperor Frederick Wilhelm in the early 20th century.

In August 2001, St. Stephens suffered a near-disastrous electrical fire. The fire began in the ceiling and smoldered for hours before employees of a nearby business saw smoke coming from the roof and alerted the church. Firefighters had to carry a hose up three flights of stairs and use catwalks that had caught on fire before they were able to reach the source of the flames.

At the recommendation of the church’s insurance company, the church elders contacted Horgan Sales and Service, Inc. in Stevens Point, Wisconsin. The company installed a VESDA Air Sampling Smoke Detection System in June 2002. It included four VESDA

“It is personally and professionally gratifying to offer this congregation an affordable technology that can prevent fire and its related losses,” said Jim Oliver, sales manager for Horgan. “In addition to gaining peace of mind, St. Stephens may well have the further satisfaction of leading the way to help others in their efforts toward heritage preservation.”

The VESDA Air Sampling Smoke Detection System can be customized to protect mezzanines, balconies, high ceilings, and beam pockets. Advanced smoke detection technology addresses the unique configurations of size, height, obstructions, airflow, need for very early warning, and cost considerations. The system provides optimum protection against fire by reliably detecting the presence of smoke at the earliest (pre-combustion) stage with continuous sampling of air. This offers the widest window of opportunity to detect and control the spread of fire.

VESDA allows for concealed detection, without disrupting internal, and often delicate, architecture. One VESDA detector replaces many traditional smoke detectors. Programmable alarm thresholds address the problems of external pollution and airflow, which can cause false alarms. Detectors are easily accessible and centrally located, allowing for servicing and maintenance of the system without the need for ladders. The level of response can be customized to provide the earliest opportunity for fire investigation. The system also interfaces with all fire alarm control panels, regardless of manufacturer.

The VESDA system utilizes “Aspire™”, a programming software package that tailors the sampling point network for each church. The sampling point network is a crucial element of an aspirating smoke detection system, and the software allows modeling during the design phase. The software predicts the performance of the proposed network, providing a cost-effective means of developing the optimum system for a particular structure.