What Are the Requirements for Smoke Evacuation Systems in Buildings?

Smoke, and the chemicals that it contains, can sometimes be more damaging and deadly than the flames from a fire, which is why many buildings have strict smoke evacuation protocols that must be met, in addition to fire suppression and alarm systems.

In a smoke evacuation system, the smoke from a fire may either be contained or directed. This means that it can be kept away from areas where occupants may need to shelter in place, from areas like stairwells where people may be escaping, and from sensitive areas where smoke may do the most damage.

Every smoke evacuation system can vary along with the building, its size, its layout and its needs. Meeting the requirements for smoke evacuation may differ based on these characteristics.

Mechanical Systems

Most commercial buildings that need some type of smoke evacuation system will use one of two types of mechanical systems to help manage the smoke. One system pressurizes specific areas, such as stairwells, which can help prevent the smoke from entering them. The other type of system helps utilize fans and exhaust systems to remove the smoke from designated areas.

Each type of system requires two sets of controls. The first is automatic and is meant to be triggered in the event of a fire. Much like a smoke alarm or a sprinkler system, the mechanical systems are designed to start working when they sense heat, particles from the smoke or flame. In addition, each system must also have a manual override, which must be easily accessible.

In the event that the fire department arrives and needs to override the system for some reason, the manual controls must be able to allow for an override. Pressurizing some systems can make it more difficult for doors to open, but having a manual override means that the fire department can reach individuals who may be sheltering in a pressurized area.

It is important to know that recent changes in the ADA (Americans with Disabilities Act) have meant that many buildings need to have a safe area designated for people who are unable to get out of the building safely by other means.

Having smoke evacuation systems in place can allow certain areas to be designated for sheltering in place. Occupants can reach these areas and stay there until the fire department or rescue personnel are able to reach them.

Smoke Baffles

An addition to most smoke evacuation systems is the smoke baffle, sometimes called a smoke curtain. These have different requirements and applications than fully deployable smoke containment systems, but their base use case is to help direct the smoke in the direction of the exhaust system.

Exhaust systems can help draw smoke, but they may not be fast enough or powerful enough to pull it all through as fast as necessary. Some smoke may be able to get into open areas where it can stain, damage materials or reach building occupants. Smoke baffles or curtains can be used in places where the smoke may naturally drift as it makes its way to the exhaust.

The curtains help to stop the smoke from entering areas near the exhaust system, which makes the exhaust system more efficient at removing the smoke.

Elevator Smoke Control

Many buildings have requirements for elevator smoke control as well in order to meet codes and regulations. This is a more difficult requirement to meet than stairway or shelter-in-place requirements since elevators are made of materials that are difficult to pressurize. In addition, the doors are not able to be as tightly sealed as a stairwell door, making it harder to stop smoke from entering.

If the elevators are not in use during a fire, the elevator shaft can still pull and funnel smoke through a building. For that reason, some form of elevator smoke control is required.

A good choice that can help block the smoke from the elevator(s) is a smoke curtain designed specifically for the elevator. Unlike stationary smoke baffles, the smoke curtains are not deployed at all times. Instead, they sit discreetly above the elevator opening until needed.

At that time, they unroll to completely cover the elevator door, effectively blocking any smoke from entering. This works more effectively than door seals or sweeps and can help contain the smoke in an area so that exhaust systems can help move it out.

Zoned Smoke Control

In some large buildings, each floor of the building may need its own zone for smoke evacuation. This is not a blanket requirement, and it varies by occupancy. If the building is indicated as requiring zones, each floor would need to be treated separately. This means that each floor would need its own mechanical system, including pressurized zones, exhaust and smoke baffles.

In addition, to help compartmentalize the smoke within each zone, different types of smoke curtains may also be used. These may deploy across atriums, around sensitive areas or across wide doorways. This can help create the targeted zone necessary for the mechanical systems to help clear the smoke.

Help Remove Smoke Effectively

Smoke evacuation systems can and do vary by building; they are a crucial part of any smoke and fire management plan. Smoke evacuation and smoke control systems can help prevent additional damage and potential loss of life caused by the smoke from a fire.

When installing a fire suppression system, evacuation plan or alarm system, make sure that you update your smoke control system, as well, to ensure the best results and safest environment in the event of a fire.

Contact the safety experts at Smoke Guard today to create a smarter and safer smoke evacuation plan.