Why healthy building standards matter right now
Healthy building standards turn best intentions into measurable outcomes. They give owners, facility managers, and occupants a common language for clean air, safer spaces, and continuous improvement. In the last few years, one standard rose to the top of every conversation about airborne risk: ASHRAE Standard 241: Control of Infectious Aerosols. The standard sets minimum requirements to reduce disease transmission in both new and existing buildings and in major renovations, and it provides a practical framework for how to design, operate, commission, and maintain systems that keep people safer. ASHRAE 241 aligns with the core promise of healthy building standards: protect people where they work, learn, and heal without disrupting daily life. It moves beyond generic ventilation advice and defines performance targets you can act on.
What ASHRAE 241 actually requires—plain English
ASHRAE 241 introduces a few ideas that matter to day-to-day operations:
1) Equivalent Clean Airflow (ECAi).
Instead of focusing only on outside air, the standard defines a target amount of pathogen-free air per person that you can meet with a combination of outdoor air, filtration, air cleaning, and inactivation (e.g., UVGI, visible-light disinfection). This lets you reach the same infection-risk reduction with the mix that fits your building.
2) Infection Risk Management Mode (IRMM).
You don’t always run a building the same way. IRMM is a higher-protection operating mode you activate during elevated community risk (e.g., a surge). It pairs with your Building Readiness Plan so you know exactly how you’ll increase clean air fast.
3) Building Readiness Plan (BRP).
The BRP documents your strategies, set points, and verification steps, so teams can implement and maintain 241 quickly and consistently.
These concepts make 241 flexible and performance-based. You can meet the target with better filters, smart air cleaners, increased outdoor air, or safe in-space disinfection lighting—whatever delivers the clean-air dose efficiently.
How 241 fits alongside CDC and other guidance
Facility leaders often ask whether 241 conflicts with CDC ventilation guidance. It doesn’t. CDC ventilation resources and 241 complement each other: CDC outlines why good ventilation and air cleaning reduce viral exposure, while 241 defines how to quantify and deliver the equivalent clean airflow needed to manage risk.
If you’ve followed ASHRAE 62.1/62.2 for baseline IAQ, 241 layers on top to address infectious aerosols specifically—turning healthy building standards into a practical playbook for elevated-risk periods.
Turning the standard into a plan for your building
Use this step-by-step approach to make 241 actionable in your portfolio:
Step 1 — Benchmark current performance.
Measure outdoor air rates, filter types and pressure drops, clean air delivery from portable or ceiling-mounted purifiers (if used), and any active disinfection systems. Translate this into equivalent clean airflow per person for representative spaces.
Step 2 — Identify the gaps.
Compare your present clean-air total to the 241 target for each space type and occupancy. Note the shortfall in cfm/person of pathogen-free air.
Step 3 — Choose the most efficient path to close the gap.
Raising outdoor air alone may be expensive in hot, humid, or very cold climates. You can close the gap more efficiently with a mix of higher-MERV filtration, in-duct or in-space air cleaning, or safe, continuous disinfection lighting.
Step 4 — Create (or update) the Building Readiness Plan.
Document how you’ll shift into IRMM when risk rises: what to activate, to what set points, and how to verify performance in hours—not weeks. Step 5 — Verify and communicate.
Validate clean-air delivery with commissioning data or third-party tests, then communicate the results to occupants. Clear signage and dashboards build trust and support.
Practical ways to meet 241 with healthy building standards
Every building is different, but these strategies commonly deliver the best cost-to-impact:
Upgrade filtration where it fits the fan curve.
Moving from legacy filters to MERV 13 or better often yields a big step up in equivalent clean airflow with modest operational impact. If static pressure becomes a constraint, combine filtration with active air cleaning.
Add safe, continuous in-space solutions.
Ceiling-mounted or integrated systems that run while spaces are occupied can add significant clean-air delivery without overhauling ducts. Illumipure’s Air Guardian family provides in-space air cleaning that contributes to ECAi while remaining quiet and low-maintenance. Pair it with Vertices AQS style monitoring to track VOCs, CO₂, and particulates in real time for operational visibility.
Use UV-free disinfection lighting where people gather.
Visible-spectrum disinfection, such as CleanWhite® LED, reduces microbial load continuously in occupied rooms, supporting both occupant safety and 241’s performance targets without UV exposure risks or occupancy restrictions. This approach aligns with healthy building standards that prioritize safety, energy performance, and usability.
Target high-risk rooms first.
Clinics, school nurses’ offices, gyms, locker rooms, break rooms, and conference spaces tend to show the highest risk and the fastest return on clean-air investments. See how similar spaces deployed solutions in our case studies.
Budgeting and energy: delivering clean air without waste
241’s performance-based design lets you optimize for lifecycle cost. Many owners find that mixing moderate outdoor air increases with efficient in-space clean-air devices beats a “ventilation only” approach on both capex and opex—especially in humid or extreme climates. Because visible-light disinfection and advanced LED purification can run continuously without occupancy limits, the building receives a steady clean-air dose without energy-intensive purge cycles.
If you run simple scenarios—outdoor air only vs. mixed strategies—you often see the mixed approach meet the equivalent clean airflow target at lower energy and with less equipment stress. That’s a win for sustainability, resilience, and budgets.
Compliance, communication, and credibility
Healthy building standards work when you verify and share results. Document your equivalent clean airflow calculations, commissioning data, filter change schedules, and IRMM playbook inside the Building Readiness Plan. Post easy-to-read summaries in lobbies, share updates with tenants, and brief your safety committee or school board. This builds confidence and helps teams respond quickly when risk levels change.
You can also reference external authorities when you educate stakeholders. CDC materials explain why ventilation and air cleaning reduce airborne exposure, and they note that ASHRAE 241 complements CDC mitigation strategies—a helpful point for leadership and legal teams.
What this means for different sectors
Healthcare. Waiting areas, clinics, and administrative zones benefit from continuous, UV-free solutions that reduce risk without impacting workflows.
Education. Classrooms, special services areas, and nurses’ offices need steady clean air all day. In-space devices plus upgraded filtration help schools meet targets without costly HVAC replacements.
Workplaces. Conference rooms, open offices, and break rooms drive infection spread. Quiet, always-on clean-air systems support attendance and productivity.
Hospitality and fitness. Group classes, locker rooms, and dining areas collect humidity, VOCs, and bioaerosols. Continuous in-space purification controls odors and risk at the source.
For examples of these environments in practice, explore Illumipure case studies.
Frequently Asked Questions
Does ASHRAE 241 replace existing ventilation standards?
No. 241 complements baseline IAQ standards (like 62.1/62.2) by addressing infectious aerosols specifically and by defining performance targets using equivalent clean airflow.
Is ASHRAE 241 recognized by public-health authorities?
CDC notes that 241 does not conflict with CDC ventilation strategies; the two complement each other. That alignment strengthens your communication with stakeholders.
How do I meet the target if my HVAC can’t push more outdoor air?
Use a mix: better filters where fans allow, plus in-space clean-air systems and safe, continuous disinfection lighting. The combined effect counts toward equivalent clean airflow and often costs less than ventilation-only upgrades.
When should I activate Infection Risk Management Mode (IRMM)?
Use IRMM during elevated community risk or outbreaks. Your Building Readiness Plan should spell out triggers, set points, and verification steps so you can act quickly.
Conclusion
Healthy building standards give you a roadmap; ASHRAE 241 gives you the performance target. When you pair the two, you protect people more effectively and use your energy dollars more wisely. If you’re ready to close the gap between where your building is today and what 241 recommends, our team can help you model options and implement safe, continuous solutions that occupants will notice for the right reasons.
Explore the technologies behind these strategies on our Technology page, see results in Case Studies, and start a tailored plan for your portfolio by contacting Illumipure
