The materials that dress a live event — drapes that mask the backstage, fabric backdrops that define the set, curtains that block unwanted light, foam that absorbs sound, fabric that covers seating — are potential fuels. In the wrong conditions, with the wrong ignition source and the wrong material, the difference between a fabric that chars slowly and one that ignites explosively can be measured in lives.

The requirement for flame-resistant materials in assembly occupancies is one of the most consequential and most frequently overlooked fire safety provisions in live event management. Understanding what the standard requires, how compliance is documented, and where flame-resistant requirements apply is essential knowledge for event producers, set designers, venue managers, and lighting directors.

The Governing Standard: NFPA 701

NFPA 701, Standard Methods of Fire Tests for Flame Propagation of Textiles and Films, establishes the test procedures used to determine whether a textile or film material meets the flame propagation performance criteria required by fire codes for use in assembly occupancies. The standard is referenced throughout the International Fire Code and NFPA 101, and meeting NFPA 701 criteria is the primary way that decorative and scenic textile materials are documented as compliant with assembly occupancy requirements (National Fire Protection Association [NFPA], 2019; International Code Council [ICC], 2021a).

NFPA 701 does not specify whether a material passes or fails based on a simple yes/no — it establishes the test methodology. The fire codes then specify the performance criteria that tested materials must meet. NFPA 101 and the IFC require that curtains, draperies, hangings, and other decorative materials suspended from walls or ceilings in assembly occupancies meet the flame propagation performance criteria of NFPA 701 (NFPA, 2021; ICC, 2021a).

What Must Be Flame-Resistant

The materials required to meet NFPA 701 criteria in assembly occupancies are more extensive than many event organizers realize. They include:

• Curtains and draperies of any type — masking drapes, blackout curtains, decorative fabric panels, backdrop curtains
• Decorative hangings — fabric-based installations suspended from walls or ceilings as decorative elements
• Combustible scenery — cloth, film, vegetation (dry), and similar materials used as stage scenery or event décor
• Motion picture screens — screens used in assembly occupancies must meet NFPA 701 criteria
• Tent fabrics — all fabric and pliable materials used in tent and membrane structures must be tested before permits are issued (NFPA, 2022c)

For decorative materials on walls or ceilings, there are also quantity limitations: combustible decorative materials attached to walls or ceilings are limited to no more than 10 percent of the wall or ceiling area to which they are attached (NFPA, 2021; ICC, 2021a). Artwork and teaching materials in corridors may be up to 20 percent of the wall area. These limits apply even when materials are tested as flame resistant — because the quantity of combustible material in a space, not only its flame resistance, affects how quickly a fire can grow.

Foam Plastic: A Specific and Critical Requirement

Exposed foam plastic materials used for decorative purposes, stage scenery, or exhibit booths are subject to specific requirements beyond NFPA 701 testing. Under NFPA 101 and the IFC, foam plastic materials weighing more than one pound (0.45 kg) must have a maximum heat release rate of 100 kW when tested according to UL 1975, Fire Tests for Foamed Plastics Used for Decorative Purposes (NFPA, 2021; ICC, 2021a).

This requirement exists because of the catastrophic failure of untested foam plastic at The Station nightclub fire in 2003. The polyurethane acoustical foam installed on the stage walls had never been tested for fire performance in an assembly occupancy context. It ignited within seconds of contact with a pyrotechnic spark and contributed to the fire spreading across the entire venue interior within minutes. Post-fire testing of the same foam material demonstrated that it propagated flame and produced heat at rates far above those permitted for assembly occupancy materials (Grosshandler et al., 2005).

The distinction between foam plastic “acoustic foam” sold for studio use and foam plastic that has been tested and approved for assembly occupancy use is critical and not obvious from visual inspection. Event producers who use foam for acoustic treatment, speaker surrounds, or decorative cladding in any assembly occupancy must verify that the specific product has been tested under UL 1975 and meets the 100 kW maximum heat release rate requirement (NFPA, 2021).

Scenery and Stage Properties

Scenery and stage properties that are not separated from the audience by proscenium opening protection must be of non-combustible materials, limited-combustible materials, or fire-retardant treated (FRT) wood (NFPA, 2021; ICC, 2021a). This requirement applies to the structural elements of scenic construction — platforms, flats, frames — not only to fabric coverings.

Fire-retardant treated wood is dimensional lumber or plywood that has been pressure-impregnated with fire-retardant chemicals that slow flame spread. It is distinguished from “fire-retardant paint” or surface coatings, which provide limited and time-limited flame resistance. FRT wood must be identified as such by a marking on the lumber or by documentation from the supplier — visual inspection alone cannot confirm that wood has been pressure-treated (NFPA, 2021).

Combustible scenery made of cloth, film, or dry vegetation must either meet NFPA 701 flame propagation criteria or exhibit a heat release rate not exceeding 100 kW when tested under NFPA 289, Standard Method of Fire Test for Individual Fuel Packages, using a 20 kW ignition source (NFPA, 2021).

The Proscenium Opening: Fire Curtains and Water Curtains

In theatre venues with a proscenium arch, the opening between the stage and the audience is a critical fire barrier. Where required by the AHJ, the proscenium opening must be protected by one of the following:

• A listed, minimum 20-minute opening protective assembly
• A fire curtain complying with NFPA 80, Standard for Fire Doors and Other Opening Protectives
• An approved water curtain complying with NFPA 13 (NFPA, 2021; ICC, 2021a)

A traditional theatre fire curtain — the heavy, fire-resistant curtain installed above the stage behind the proscenium — serves as a barrier that separates a stage fire from the audience. Where a fire curtain is present, it must be inspected and tested at regular intervals to confirm that it will actually deploy when needed. A fire curtain that has been permanently attached to staging equipment or blocked by rigging infrastructure is not operational and provides no protection.

Proscenium opening protection other than a fire curtain — such as a water curtain spray system — must activate automatically upon fire detection in the stage area and must also have manual activation capability (NFPA, 2021).

Documenting Compliance

The AHJ may require documentation of flame resistance before permitting the use of specific materials in an assembly occupancy. Documentation typically takes one of two forms:

• Certificate of flame resistance: a document from the material manufacturer or an approved testing laboratory certifying that the material has been tested to NFPA 701 criteria and meets the required flame propagation performance. This should be retained on file and available for inspection.
• Material sample testing: the AHJ may require that a sample of the actual material to be used — not the manufacturer’s representative sample — be tested before use. This is more common for custom or unusual materials not covered by standard product certifications.

For tent fabrics, NFPA 102 and the IFC require that the tent permit applicant provide a certificate executed by an approved testing laboratory certifying that all tent fabric, sidewall, and appurtenance materials meet NFPA 701 flame propagation criteria before a permit to erect is issued (NFPA, 2022c; ICC, 2021a). This certificate must be for the specific fabric used in the tent being erected — not a generic certification for the tent manufacturer’s product line.

Field-Applied Flame Retardants

Fabrics that do not inherently meet NFPA 701 criteria may be treated with field-applied flame retardant chemicals. However, field treatment is not a reliable substitute for factory-tested, inherently flame-resistant materials. The effectiveness of field-applied treatments degrades over time, particularly after laundering or exposure to moisture. Field treatments may not penetrate thick or densely woven fabrics adequately. Where field-applied treatment is proposed, the AHJ should be consulted about acceptable application and verification methods (NFPA, 2019).

References

Grosshandler, W. L., Bryner, N., Madrzykowski, D., & Kuntz, K. (2005). Report of the technical investigation of The Station nightclub fire (NIST NCSTAR 2). National Institute of Standards and Technology.

International Code Council. (2021a). International fire code. ICC.

National Fire Protection Association. (2019). NFPA 701: Standard methods of fire tests for flame propagation of textiles and films. NFPA.

National Fire Protection Association. (2021). NFPA 101: Life safety code. NFPA.

National Fire Protection Association. (2022c). NFPA 102: Standard for grandstands, folding and telescopic seating, tents, and membrane structures. NFPA.

Underwriters Laboratories. (2019). UL 1975: Fire tests for foamed plastics used for decorative purposes. UL Standards & Engagement.