TLDR: Theater curtains should be tested annually as a part of your theatrical rigging inspection. We offer it for free with our rigging inspections.
Theatrical curtains serve a dual purpose: they create atmosphere and storytelling magic onstage, but they’re also a vital part of a venue’s fire protection system. Whether in a school auditorium, professional theatre, or multipurpose venue, these curtains must meet strict fire safety standards to protect performers, staff, and audiences.
We break down how often theatrical curtains should be tested, the difference between field and lab testing, how the testing is performed, and what standards apply to keep your venue in compliance.
How Often Are Theatrical Curtains Required to Be Tested?
Curtains treated with flame retardant must be tested at least once every 12 months to verify continued compliance with fire codes. Over time, flame-retardant chemicals can degrade due to humidity, dust, UV exposure, or cleaning, reducing the curtain’s fire resistance.
Best practice:
- Annual field testing per NFPA 705
- Third-party lab testing every 3–5 years using NFPA 701-certified methods in a test chamber
- Immediate re-treatment or replacement if a curtain fails any test. Immediate test after re-treatment.
Some AHJs or state fire codes may require lab testing for public venues with high occupancy or complex fire protection systems. Always verify with your local fire marshal.
Field vs. Laboratory Flame Testing
There are two recognized methods for testing flame retardancy in curtains:
1. Field Flame Test – NFPA 705
Used for in-place testing without removing the curtain. A sample is cut and exposed to flame under controlled conditions:
- Sample: 1.5” x 4” swatch from the curtain
- Apply flame for 12 seconds
- The fabric must self-extinguish within 2 seconds and not drip flaming particles
This test confirms that the treatment is still effective in the real-world condition of your curtain.
2. Laboratory Test Chamber – NFPA 701
For formal certification, materials are tested under controlled laboratory conditions using vertical flame test chambers:
- Material is exposed to calibrated flame sources
- Ignition behavior, flame spread, smoke development, and after-flame time are recorded
- Results determine whether the fabric complies with Type I or Type II criteria
This is the only method recognized for original manufacturer certification and is required for new curtains, treated fabrics, or re-certification in high-risk venues.
Labeling and Documentation Requirements
After a successful flame test (either in the field or in a lab), the curtain must have a permanent flame certification label affixed. According to code and industry best practices:
- Label must be sewn into the curtain’s lower edge; typically, the bottom left or right corner
- Must include:
- Date of last test
- Flame-retardant chemical used
- Testing method and pass result
- Name of the certifying company or technician
Lack of a current label is a common violation during fire marshal inspections and may require immediate removal or replacement of the curtain.
Applicable Codes and Standards
- NFPA 701: Standard Methods of Fire Tests for Flame Propagation of Textiles and Films – lab certification
- NFPA 705: Field Flame Test for Textiles and Films – annual on-site verification
- OSHA 29 CFR 1910.39: Requires fire prevention plans that
- ASTM E84: Standard Test Method for Surface Burning Characteristics of Building Materials
Additional Safety Considerations
- Dry cleaning or washing curtains can remove flame retardant. Always retest after cleaning. This may also shrink curtains so it is not recommended unless the curtain fails the retardant test or the curtains are exceptionally dirty.
- Curtain hardware should be visually inspected as part of your annual rigging inspection. This is particularly important for elementary and middle schools that do not typically have a counterweight rigging system. We often inspect all the schools that feed a high school when we inspect a high school.
- Stage personnel must be trained to recognize and report deteriorated or damaged draperies.
Take Action Now
If your curtains haven’t been tested this year, you may be out of compliance. Schedule a flame test or request re-treatment as needed. Partner with a qualified vendor that provides:
- On-site NFPA 705 testing
- Off-site NFPA 701 lab certification
- Flame-retardant re-treatment with documentation and labeling
Sometimes it’s just best to replace curtains. All fabricators should be members of ESTA and USITT. We recommend the following and often include the BOLD names as pre-approved when we write specs. This list is not comprehensive it’s simply a list of some of our favorites.
As an independent, impartial, consulting firm, we are unable to accept any compensation for our recommendations.
| Manufacturer | Website URL |
|---|---|
| BellaTEX, Inc. | https://bellatex.com/ |
| Dazian Event Fabrics & Drapery | https://www.dazian.com/stage-drapery/ |
| Drape Kings | https://www.drapekings.com/ |
| Georgia Stage | https://www.gastage.com |
| Kenney Drapery Associates, Inc. | https://kenneydrapery.com/ |
| Norcostco | http://www.norcostco.com |
| Northeast Stage | https://northeaststage.com/ |
| Rose Brand | https://www.rosebrand.com/ |
| S&K Theatrical Draperies | https://www.sktheatricaldraperies.com/ |
| Sew What? Inc. | https://sewwhatinc.com/ |
| ShowTex (Global) | https://www.showtex.com/ |
| Stagecraft Industries | https://www.stagecraftindustries.com/curtains |
| Syracuse Scenery & Stage Lighting | https://syracusescenery.com |
| Texas Scenic Company | https://www.texasscenic.com/products/curtains/ |