Improved Respiratory Protection for CBRN Response

Summary

The NIOSH Respirator Approval Program works to improve respirators that protect against CBRN hazards (see the NIOSH CBRN Handbook). Much of this work began after several major terrorist incidents in the mid-1990s and early 2000s. The Oklahoma City Alfred P. Murrah Federal Building bombing, the 2001 anthrax attacks, and the September 11, 2001, attacks on the World Trade Center and Pentagon all revealed critical gaps in respiratory protection for emergency responders.1

Responses to the Oklahoma City, World Trade Center, and Pentagon terrorist attacks were complicated by the presence of many hazards ranging from burning fuel and dust to heat and explosions.1 The exposures and resulting illnesses from the September 11, 2001, event underscored the need for respirators better able to protect against unknown hazards. In response, NIOSH strengthened its Respirator Approval Program by:

• Researching responder CBRN hazards,
• Developing CBRN standards,
• Conducting rigorous performance testing, and
• Evaluating products before and after market entry.

Background

During many types of emergencies, including terrorist attacks, emergency responders may be exposed to hazardous materials and toxic chemicals for long periods. If first responder organizations are not fully prepared, responders may have to rely on personal protective equipment (PPE) that is designed for shorter use times, such as typical firefighting gear.1 Evidence shows that during the 9/11 response, prolonged exposure to airborne dust, smoke, and toxic substances contributed to both immediate and long-term health effects among responders. In one study, workers that used respirators self-reported fewer respiratory symptoms/diseases than responders that reported no respirator use or use of disposable masks.2

The 9/11 responders on the scene of the attacks continue to face a range of health problems due to various exposures, including:

• Inhaling dust, smoke, and toxic substances,
• Inhaling particulate matter and irritants, and
• Experiencing prolonged exposure to carcinogenic substances.

Some of the responder health issues that might have been mitigated by proper respiratory protection include, but are not limited to:

• Respiratory and lung diseases, including asthma, chronic bronchitis, and Reactive Airway Dysfunction Syndrome (RADS),
• Gastroesophageal Reflux Disease (GERD),
• Cancers, including lung cancer, thyroid cancer, and multiple myeloma,
• Sinus and nasal problems, including chronic sinusitis.
• (See the World Trade Center Health Program topic pages on 9/11 exposures and Health Effects of 9/11: An Online Exhibition for more information.)

These health problems have led to ongoing medical monitoring and support programs for the affected responders. One of these is the World Trade Center Health Program, which provides medical monitoring and treatment for those impacted by the 9/11 attacks.

What NIOSH is doing

The NIOSH Respirator Approval Program works to improve respiratory protection for emergency responders, including self-contained breathing apparatuses (SCBA) and air-purifying respirators (APR).

Understanding hazards and standards development

NIOSH studies the specific dangers responders might face during a CBRN event, including emerging hazards.

NIOSH defined and adopted requirements for respirators that provide protection against CBRN hazards. Further, NIOSH contributes to voluntary consensus standards (e.g., NFPA) that incorporate these requirements. NIOSH Approved®A CBRN respirators may be suggested as part of a firefighter, hazardous material, or emergency response ensemble as described in National Fire Protection Association standards.

Performance testing and pre- and post-market activities

NIOSH conducts rigorous testing during the NIOSH approval process to ensure that respirators meet strict performance requirements. NIOSH requires chemical warfare agent testing for respirators providing CBRN protections.

NIOSH evaluates respirator designs before approval and conducts ongoing audits, investigations, and hazard assessments after products enter the market.

Collaborating

NIOSH collaborates with partners to ensure respirator performance and use requirements address the real-world exposures and operational demands faced by responders. Organizations that contribute to these efforts include the:

• International Association of Fire Fighters,
• International Association of Fire Chiefs,
• Occupational Safety and Health Administration,
• Department of War, and
• Department of Homeland Security.

The impact

NIOSH's efforts have led to significant improvements in respirators with CBRN protections, making emergency responders safer. Some key achievements include:

• NIOSH has approved over 400 respirators with CBRN protections.
• NIOSH expanded the NIOSH CBRN APR Canister Protection List from 139 hazards in 2018 to 286 hazards in 2021.
• NIOSH partnerships with industry leaders have spurred innovative design through research and standards development.
• NIOSH is planning for an update to 42 CFR 84 to include requirements for new industry developments such as combination unit respirators (CUR) that provide both self-contained breathing capabilities and air-purifying functions.

What's next

NIOSH is committed to continuing its service, research, and standards development to keep responders safe by:

• Optimizing the evaluation and approval of new CBRN respirator models to enhance supply chain resilience and increase the availability of NIOSH Approved respiratory protection for responders.
• Evaluating and auditing products on the market and manufacturing sites to ensure NIOSH Approved respirators continue to meet the conditions of the approval.
• Developing and continuously refining PPE documents to provide responders with the most current, evidence-based protection strategies (see the CBRN handbook linked below).
• Assessing new and evolving CBRN hazards to ensure responders have the best protection available.

For more information, emergency responders and stakeholders should refer to the NIOSH CBRN Respiratory Protection Handbook. NIOSH updated this handbook in May 2025. A recent NIOSH science bulletin summarizes these updates. The update includes the expansion of the CBRN APR Canister Protection list mentioned above.

NIOSH is dedicated to keeping first responders safe while they perform their critical duties in the face of CBRN hazards. Maintaining a robust Respirator Approval Program, conducting research, contributing to consensus standards, and collaborating with partners help ensure that first responders have the most reliable and effective respiratory protection against CBRN hazards.

Author information

Justin Wehring, MHA, is a Health Communication Specialist in the NIOSH Division of the National Personal Protective Technology Laboratory (NPPTL).

Jeffrey Peterson is the Branch Chief of the Conformity Verification and Standards Development Branch in the NIOSH Division of the National Personal Protective Technology Laboratory (NPPTL).

Jaclyn Cichowicz, MA, is Lead Health Communication Specialist in the NIOSH Division of the National Personal Protective Technology Laboratory (NPPTL).