The Air Your Performers Breathe Just Got Regulated. Here Is What Changed
Actors’ Equity’s 2024 fog and haze overhaul is the most significant update in over two decades. If you produce, design, or manage theatrical productions, this affects you now.
Every lighting designer knows the feeling. The haze catches a side-light wash just right and the whole stage becomes three-dimensional. It is one of the most powerful tools in our visual vocabulary. But that tool just got new rules, and they are more specific than anything we have seen since the original Mount Sinai study landed on Broadway producers’ desks in 2000.
In 2024, Actors’ Equity Association completed a comprehensive overhaul of its smoke, fog, and haze regulations. Updated Time and Distance charts, revised calibration factors, and clarified compliance expectations are now baked directly into current Equity contracts, including the 2023 to 2027 LORT agreement (Actors’ Equity Association, 2024a). This is not a subtle policy tweak. It is a rewrite of the operational framework that governs atmospheric effects on every Equity stage in the country.
If you are a production manager, technical director, master electrician, or designer working under any Equity agreement, here is what you need to know and what you need to do about it.
Why This Matters Now
The regulations trace back to a single foundational document: the Mount Sinai School of Medicine and ENVIRON International Corporation study titled “Health Effects Evaluation of Theatrical Smoke, Haze, and Pyrotechnics,” commissioned by the Equity-League Pension and Health Trust Funds and released in 2000 (Moline & Golden, 2000). That study examined Broadway performers and found a clear association between elevated peak exposures to glycol and mineral oil aerosols and increased respiratory and mucous-membrane symptoms, particularly among chronically exposed performers.
Independent research confirmed the concern. Varughese et al. (2005) studied 101 entertainment industry employees across 19 sites in British Columbia and found that chronic work-related wheezing and chest tightness were significantly associated with increased cumulative exposure to theatrical fog aerosols. Their data showed that exposure levels were higher with mineral oil products, when multiple fog machines were in use, and among workers positioned closest to the discharge point.
The science has been consistent for over two decades. What changed in 2024 is that Equity tightened the operational framework around that science and closed several compliance gaps that producers had been navigating with varying degrees of rigor.
The Three Major Updates
1
Revised Time and Distance Guidelines. Ramboll (formerly ENVIRON) developed updated T&D tables approved by both Actors’ Equity and the Broadway League. These tables specify the minimum wait time and distance from the discharge point for each tested machine, fluid, and attachment combination. If your specific combination appears in the chart, and you follow the cue length, distance, and wait-time parameters exactly, no additional air sampling is required (Ramboll, 2024). The tables were developed under conservative assumptions, including cue release at breathing height with no enhanced dispersion from on-stage activity (ENVIRON International Corporation, 2001).
2
Updated Calibration Factors. Equity released a revised Calibration Factors technical memo in April 2024. This document specifies the correction factors required when using a portable aerosol monitor to verify compliance. These factors account for the difference between the monitor’s optical particle-sizing response and the actual mass concentration of a given product’s aerosol (Actors’ Equity Association, 2024b). Without the correct calibration factor, raw monitor data is meaningless for compliance purposes.
3
Clarified Compliance Expectations. Equity’s regulations page and FAQ were overhauled to eliminate ambiguity. The most consequential clarification: products marketed as “water-based” are not exempt from reporting or exposure-limit rules. All fog, haze, and smoke products are treated as combinations of water plus glycol, mineral oil, or glycerol, and must still fall within the published guidance levels (Actors’ Equity Association, 2024c).
The Exposure Limits You Must Know
The peak exposure guidance levels remain anchored to the original Mount Sinai/ENVIRON study. These are the numbers your production cannot exceed at the point where performers are staged or choreographed:
| Substance | Peak Exposure Limit | 8-Hour TWA |
|---|---|---|
| Glycol | 40 mg/m³ | — |
| Glycerol | 50 mg/m³ | 10 mg/m³ |
| Mineral Oil | 25 mg/m³ | 5 mg/m³ |
These guidance levels were designed to minimize potential health impacts, not eliminate all risk. The Mount Sinai study found that as long as peak exposures were avoided, performers’ health, vocal abilities, and careers should not be harmed (Moline & Golden, 2000). The word “should” is doing meaningful work in that sentence. The regulatory thrust is precautionary: keep exposures below the peaks, verify that you have done so, and document everything.
Critical Note on Monitoring Equipment: Actors’ Equity is aware that the PDR-1000AN aerosol monitor manufactured by Thermo Fisher Scientific has been discontinued, including all spare parts and service support. Discussions are underway to approve new aerosol monitors. In the interim, Equity recommends renting rather than purchasing the PDR-1000AN. If the monitor is unavailable, productions must strictly adhere to the T&D charts (Actors’ Equity Association, 2024a).
Two Paths to Compliance
The 2024 framework gives producers two options, and only two.
Path One: Follow the T&D Charts
If your exact machine, fluid, and attachment combination appears in the approved T&D tables, and your cue length, performer distance, and wait time match the chart parameters, you are compliant. No air sampling is necessary. This is the simpler path, but it requires precision. You cannot mix and match machines and fluids outside the tested combinations. Each row of the chart represents a specific, tested configuration (Actors’ Equity Association, 2024c).
Path Two: Conduct Air Sampling
If your usage falls outside the T&D parameters, or your machine/fluid/attachment combination does not appear in the charts, you must conduct on-site air sampling using a calibrated portable aerosol monitor. The monitor must be placed at the location where the closest performer will be staged. Multiple readings before, during, and after each cue are required to establish a median result. The calibration factor for your specific product must be applied, and the complete data set must be submitted to Equity at safety@actorsequity.org (Actors’ Equity Association, 2024a).
Air sampling must commence the first day effects are introduced to the stage, and in no event later than technical rehearsals.
How ANSI E1.5 Fits Into the Picture
Alongside the Equity framework, ANSI E1.5-2009 (R2024), “Entertainment Technology: Theatrical Fog Made With Aqueous Solutions of Di- and Trihydric Alcohols,” provides the industry consensus standard for fog composition and exposure limits (Entertainment Services and Technology Association [ESTA], 2024). This standard, developed by ESTA’s Fog and Smoke Working Group, specifies acceptable chemical components and sets a time-weighted average of 10 mg/m³ for total glycol concentration, a short-term exposure limit of 40 mg/m³ for glycol, and a ceiling of 50 mg/m³ for glycerol products.
Actors’ Equity references ANSI standards as applicable where Equity agreements do not explicitly define a requirement. The 2024 ANSI E1.5 reaffirmation confirms the standard remains current and enforceable as the baseline for theatrical fog composition nationally (United States Institute for Theatre Technology, 2024). For productions operating outside Equity jurisdiction, ANSI E1.5 remains the authoritative safety reference.
Note that ANSI E1.5 is limited to glycol and glycerol fogs. Mineral oil haze, cryogenic effects (dry ice, liquid CO₂, liquid nitrogen), and pyrotechnic smoke fall outside its scope and require separate risk assessment under the Equity study framework or other applicable standards.
What This Means for Your Next Production
In practical terms, the 2024 updates shift the burden of proof squarely onto the producer. The framework is no longer “use fog and hope nobody complains.” It is a documented compliance system that requires selection, verification, notification, and reporting at every step.
Your Compliance Checklist
- Select approved combinations only. Use machines, fluids, and attachments that appear in the Equity-approved T&D charts. If your preferred product is not listed, you are committing to the air-sampling path before you start tech.
- Design your cues to the charts. Stage and choreograph performers outside the restricted zones for the specified wait times. Build this into your blocking from the start, not as an afterthought during tech.
- Calibrate or comply exactly. If you air-sample, use the correct calibration factor from the April 2024 memo. If you follow the T&D charts, follow them precisely. There is no partial-credit option.
- Notify Equity in writing. Report your smoke and haze effects to your Field Representative using the contract-specific report form. This must happen no later than technical rehearsals, and must be updated if any cues or products change.
- Post the callboard notice. After completing either T&D compliance or air sampling, post a notice on the actors’ callboard confirming compliance. Re-post if cues or products change.
- Document everything. Retain your T&D chart references, air sampling data, calibration records, and Equity correspondence. If a performer files a complaint, your documentation is your defense.
The Bottom Line
Atmospheric effects are not going away. Equity is not trying to ban fog. The regulatory philosophy is clear: limit peak exposures through engineering controls like positioning, cue design, and ventilation; verify compliance through either pre-tested T&D charts or calibrated air sampling; and keep the union formally in the loop (Ramboll, 2024).
What is changing is the tolerance for ambiguity. The “water-based means safe” assumption is dead. The “we have always used this fluid” justification is insufficient. The expectation now is documentation, specificity, and accountability.
For those of us who care about both the art and the people who make it, this is a welcome development. Beautiful stage pictures and safe working environments are not competing interests. They never were. The 2024 updates simply make that principle enforceable.
References
Actors’ Equity Association. (2024a). Theatrical smoke and haze regulations. https://www.actorsequity.org/resources/producers/safe-and-sanitary/smoke-and-haze/
Actors’ Equity Association. (2024b). Theatrical smoke, fog and haze testing: Calibration factors (Rev. April 15, 2024). https://www.actorsequity.org/docs/librariesprovider2/resource-documents/safe-sanitary/calibration-factors-revised-2024-04-15.pdf
Actors’ Equity Association. (2024c). Smoke and haze FAQs. https://www.actorsequity.org/resources/producers/safe-and-sanitary/smoke-and-haze/faqs
Entertainment Services and Technology Association. (2024). ANSI E1.5-2009 (R2024): Entertainment technology—Theatrical fog made with aqueous solutions of di- and trihydric alcohols. American National Standards Institute.
ENVIRON International Corporation. (2001). Equipment-based guidelines for the use of theatrical smoke and haze. Prepared for the Equity-League Pension and Health Trust Funds. https://lort.org/assets/documents/Equipment-Based_Guidelines_for_the_Use_of_Theatrical_Smoke_and_Haze.pdf
League of Resident Theatres. (2023). 2023–27 LORT-AEA collective bargaining agreement. https://lort.org/assets/documents/2023-27-LORT-AEA-Collective-Bargaining-Agreement.pdf
Moline, J. M., & Golden, A. L. (2000). Health effects evaluation of theatrical smoke, haze, and pyrotechnics. Mount Sinai School of Medicine and ENVIRON International Corporation. Prepared for the Equity-League Pension and Health Trust Funds.
Ramboll. (2024). Theatrical smoke, fog, and haze testing: Time and distance guidelines (Rev. April 7, 2024). https://lort.org/assets/documents/TD-guidelines-revised-2024-04-07-1.pdf
United States Institute for Theatre Technology. (2024). ESTA announces new standards reaffirmations. USITT News. https://www.usitt.org/news/esta-announces-new-standards-reaffirmations
Varughese, S., Teschke, K., Brauer, M., Chow, Y., van Netten, C., & Kennedy, S. M. (2005). Effects of theatrical smokes and fogs on respiratory health in the entertainment industry. American Journal of Industrial Medicine, 47(5), 411–418. https://doi.org/10.1002/ajim.20151