“Smoke barrier” and “smoke partition” sound similar, but they are two unique installations that serve specific purposes.
Both smoke barriers and smoke curtains are part of a passive smoke control system and are used to help prevent the spread of smoke during a fire. They can be the key to giving occupants enough time and safe passage during an emergency evacuation.
But each performs different functions, and it’s important to understand the distinction between the two when designing a new building or renovating an old one to bring it up to code.
What Does “Smoke Barrier” Mean?
A smoke barrier’s primary function is to restrict the movement of smoke from one compartment to another. They are typically continuous surfaces that run wall to wall and floor to ceiling, often covering the running of the building.
Smoke barriers must be fire resistant and are usually constructed in the same manner as a fire barrier. Essentially, they act as a basic fire barrier but with added smoke protection to prevent the leakage and spread of hazardous air.
What Is a Smoke Curtain?
Smoke curtains, also known as smoke partitions, are a barrier to smoke but are more flexible.
Smoke curtains are perfect for areas like corridors or elevator lobbies that do not need to be fire-rated but still need smoke protection. Smoke curtains are not structural and can be deployed when smoke is present and hidden away when not in use. Because of this, smoke curtains can be installed virtually anywhere.
What Is the Key Difference Between the Two?
Both smoke barriers and smoke curtains are a part of a passive smoke management system, and both play an integral role in delaying and preventing the spread of smoke and keeping evacuation routes clear for safe egress.
However, the International Building Code (IBC) differentiates between smoke barriers and smoke curtains by requiring a fire-resistance rating for smoke barriers.
According to the IBC, a smoke barrier must have a minimum fire-resistance rating of one hour, though it may extend well beyond that minimum. Depending on the occupancy and building type, a higher fire-resistance rating may be required. Smoke barriers must also be constructed in the same manner as fire barriers but with added smoke passage protection.
Smoke barriers are also required to be sealed at all edges, regardless of positioning. If some type of penetration is required, like for an HVAC system, it must be protected on either side with dampers that automatically close at the detection of any smoke in the air.
Any doorway within the smoke barrier must be flame resistant for at least 20 minutes and must close automatically.
A smoke curtain has no minimum fire-resistance rating requirement but is tested against 400 degrees Fahrenheit or higher to pass the UL 1784. It is common to see smoke curtains that meet a 30-minute smoke resistance rating or more. They also do not have any structural requirements.
The edges of smoke curtains do not need to be sealed but must be tight-fitting against the ceiling to help prevent smoke from leaking.
Smoke curtains are more commonly used in corridors as deployable, single-paneled protection to further compartmentalize at-risk areas.
How Smoke Rated Curtains Can Act as Passive Smoke Barriers
Just because smoke curtains are not required to be fire-resistant does not mean that they aren’t. Here at SG Architectural Specialties, we offer several smoke curtains with fire ratings up to four hours. We even have smoke curtains that seal when deployed to meet all the requirements of a smoke barrier.
It is especially common in buildings with a more modern, open concept design to see smoke curtains replace traditional smoke barriers to keep as much open space as possible. Smoke curtains automatically deploy and seal off at-risk areas and evacuation routes from smoke and fire passage.
How Smoke Curtains Are Being Used as Effective Smoke Barriers
Our smoke and fire curtains have been used in several applications as effective alternatives to the traditional smoke barrier. Here are a few of our favorite examples.
Atriums add a sense of beauty and connectedness to a structure, but they create the perfect funnel for smoke to spread rapidly and can devastate a budget when trying to make them code compliant.
A smoke curtain like the Smoke Guard M4000 perimeter curtain is perfect for shielding atriums, grand staircases and even elevator lobbies from smoke or flames in the event of an emergency. This particular curtain is also fire-rated and can protect openings up to 15 feet in drop length and 220 linear feet wide.
The Smoke Guard M4000 is currently used at the Facebook Offices in Playa Vista, California in order to maintain the open-concept aesthetic while adhering to the fire safety codes.
Building safety codes have grown and changed a lot over the years as new technologies are developed to enhance fire and smoke safety measures. So, older structures, especially historic buildings, often are not compliant with today’s codes.
But the real challenge is bringing the building up to modern regulations while maintaining the integrity and historical features of the original structure. It can become too expensive — or simply impossible — to add traditional smoke barriers and not completely change the layout or architecture.
But fire-rated smoke curtains, like the Smoke Guard M2500 curtain, can be discreetly installed to bring any building up to code. Smoke curtains are virtually invisible when not in use and can be used in open areas and above doorways to meet modern fire and smoke regulations.
Fire-rated smoke curtains make sure valuable historic treasures are preserved for future generations to enjoy and cherish.
Smoke barriers are typically thought of as vertical walls to prevent smoke from spreading from room to room. But it is also important to prevent smoke from traveling to other floors as well. Spaces like stairwells and elevators operate like a chimney during a fire and are often the areas where smoke travels the fastest.
Obviously, it is not possible to have permanent barriers separating floors because then no one could travel between them.
Smoke curtain solutions, like the Smoke Guard M3000 curtain, is a fire-rated assembly designed to function as a horizontally deploying opening protective between floors and allows for compartmentalization of large spaces such as stairwells or atriums, drastically reducing the spread of smoke and flames between levels.
These fire-rated smoke curtains are most popular in places like atriums or light wells to seal off upper floors from smoke and flames to protect confined occupants until they can be properly evacuated.