VESDA and OSID smoke detection

Some spaces are hard to protect with ordinary ceiling smoke detectors: data rooms with high airflow, warehouses and atriums with tall ceilings, heritage interiors and places where detectors are hard to reach. We design aspirating smoke detection and open-area imaging beam detection for those spaces, integrated with the building's fire alarm system and set up so the early warnings they give actually reach someone.

VESDA and OSID are trademarks of their owners, Xtralis, now part of Honeywell. They are the best-known names for two technologies: aspirating smoke detection, which draws air from the protected space through a pipe network to a sensitive detector, and open-area imaging beam detection, which watches light beams across a large space for the effect of smoke. Other manufacturers make aspirating detectors as well. Our design work describes what the system must do, and the products are chosen to suit the space and your existing fire alarm system.

What we design and build

Aspirating smoke detection for data centres, server and telecom rooms, electrical rooms, clean rooms, cold storage, heritage spaces and areas where detectors must be kept out of reach.
Open-area imaging beam detection for warehouses, atriums, arenas, hangars, manufacturing halls and other large or tall open spaces.
Pipe network design: pipe routes, sampling hole locations and sizes, capillary sampling points and modelling of transport time and sensitivity.
Emitter and imager layouts: mounting positions, coverage, and checks for obstructions, structure movement and sunlight.
Alarm levels and responses: what each threshold means, who is told and what they do.
Fire alarm integration: connections to the existing control unit, annunciation, monitoring and interfaces with suppression or HVAC shutdown.

Both technologies report to the building's fire alarm control unit, like any other initiating device. The difference is that an aspirating system can also give staged early warnings before smoke reaches a fire alarm level, and those warnings need a destination and a plan.

Early warning needs a destination. Both detector types report alarm and trouble to the fire alarm control unit, which signals the monitoring centre and the annunciator. The aspirating system's earlier, lower thresholds (dashed) go to facility staff so they can investigate before a fire alarm is reached.

How it works

We start with why. Is the goal to protect irreplaceable equipment, detect smoke in a space where ordinary detectors cannot work, keep detectors out of reach, or meet an insurer's request? The answer shapes which technology fits and how sensitive it should be.
Site survey. We look at the space, airflow, ceiling height, structure, obstructions, dust and humidity, access for maintenance and the existing fire alarm system. For data rooms we note where air is supplied and returned, because that is where smoke will go.
Design. We lay out the pipe network or the emitter and imager positions, model the pipe network with the manufacturer's design tools, set alarm thresholds and responses, and define the connections to the fire alarm system. Drawings for permit are sealed by a licensed professional engineer where required, and the design follows CAN/ULC-S524 and the manufacturer's listing.
Coordinate the installation. Installation is done by qualified fire alarm technicians with recognised certification, with electrical work by licensed electrical contractors under permit. We review submittals and answer field questions.
Commissioning and verification. The system is tested with smoke at the sampling points or across the beams, transport times are measured, and the fire alarm system is verified to CAN/ULC-S537 by a qualified verifying technician. We review the results against the design.
Handover. We walk your staff through what each alarm level means, what to do, and what the ongoing inspection and maintenance under CAN/ULC-S536 and the manufacturer's instructions involve.

What to have ready

Floor plans and reflected ceiling plans of the space, and any existing fire alarm drawings.
The fire alarm control unit make and model, and its spare capacity.
For data rooms, the cooling layout: where supply and return air are, and any containment.
Your insurer's requirements, if any, and any previous fire or false alarm history.
Who will respond to early warnings, during and outside business hours.

Two technologies, two kinds of space. On the left, an imaging beam runs high across a tall open space and detects the smoke plume as it rises through the beam. On the right, an aspirating pipe under the server room ceiling draws air in through sampling holes to the detector on the wall.

What you get

A design package that your fire alarm contractor can price and install from: layout drawings, pipe network calculations or beam coverage checks, alarm threshold settings with a written response for each level, interface details for the fire alarm control unit, and a commissioning and test plan. After installation we provide a review of the commissioning and verification results against the design, and a short operating guide for your staff.

If you already have an aspirating or beam system that produces nuisance alarms or that nobody understands, we can review it: check the pipe network or beam layout against the space as it is now, compare thresholds with how the space is used, and recommend changes.

Who it's for

Data centre and server room owners who want warning before equipment is damaged.
Owners of warehouses, distribution centres, atriums and arenas with high ceilings.
Heritage and museum buildings where detectors must be discreet.
Facilities where detectors are hard to reach for testing, such as cold storage, prisons or high-bay manufacturing.
Facility managers dealing with nuisance alarms from an existing very early warning system.

For more background, read how aspirating smoke detection works, open-area beam smoke detection and where very early smoke detection makes sense. For the wider system, see our fire alarm system design service.

How this fits with mandated inspections. Aspirating and beam detectors are part of the fire alarm system, so they are covered by the annual inspection and testing under CAN/ULC-S536 that your fire code requires, done by qualified technicians. Our design and review work supports that process; it does not replace it.

Common questions

Is aspirating detection required by code?

Building codes set when a fire alarm system and smoke detection are required, but they rarely require aspirating detection specifically. It is usually chosen because the space or the risk calls for it, or because an insurer or owner wants earlier warning. Check the code adopted in your province.

Can these systems connect to our existing fire alarm panel?

Usually, as long as the control unit has capacity and compatible inputs. We check this during the survey.

Do they cause more false alarms?

A sensitive system set up badly will. A well-designed one, with thresholds matched to the space and early levels going to staff rather than straight to evacuation, gives fewer nuisance alarms than spot detectors in the same difficult conditions.