Selecting the Right CBRN Air Filtration System

In an increasingly uncertain world, the responsibility to protect yourself and your loved ones from Chemical, Biological, Radiological, and Nuclear (CBRN) threats is no longer the domain of governments alone. Private individuals and organisations are increasingly investing in all-hazard shelters designed to offer safety in the face of a wide range of catastrophes. A reliable CBRN air filtration system is the cornerstone of an all-hazard shelter, delivering clean, breathable air in the presence of toxic atmospheres due to nuclear fallout, chemical releases, smoke, or biohazards. This article provides a comprehensive guide to selecting the right CBRN filtration system, emphasizing key considerations for airflow volume, performance, reliability, and long-term readiness.

Why CBRN Filtration Systems Are Unique

Unlike most products that degrade with use over time, a CBRN air filtration system is expected to remain on standby for years—possibly decades—without being used, and yet perform flawlessly the moment it's needed. Whether facing nuclear fallout, chemical agents, biological contaminants, wildfire smoke, or industrial toxins, the system must deliver clean, safe air into a sealed environment with zero margin for failure.

This unique requirement demands careful evaluation of both the manufacturer and the system’s specifications to ensure reliability under extreme conditions.

Step 1: Evaluating the Manufacturer

The first step in selecting a CBRN filtration system is to assess the manufacturer’s credibility and expertise. Key questions to consider include:

• Experience and Reputation: How long has the manufacturer been in the industry? Established companies with a proven track record are more likely to produce reliable systems.

• Production Capacity: How many systems or filters does the manufacturer produce annually? High production volumes often indicate robust manufacturing processes.

• Product Range: Does the manufacturer offer a variety of system sizes to meet diverse shelter requirements?

• Quality Assurance: What quality control measures are in place? Are the systems subject to regular audits by governments or third-party organizations?

• Certification: Are the products certified, and if so, when and by whom? Certifications should be current, as outdated certifications may not reflect changes in materials, design, or manufacturing processes that could affect performance.

Choosing a manufacturer with rigorous quality standards and up-to-date certifications ensures the system’s reliability when it matters most.

Step 2: Determine Your Required Airflow

Once you've identified a credible manufacturer, the next step is to determine the appropriate system size for your shelter. Airflow requirements can be calculated using three key parameters. Always use the highest resulting value to ensure adequate capacity.

1. Airflow per Person

Estimate the total airflow by multiplying the number of occupants by the airflow needed per person. Common standards recommend 3–6 m³/h per person, with 6 m³/h per person preferred for civil defense or private shelters, especially in warm climates. Military shelters may require up to 17 m³/h per person, due to higher activity levels.

Example: 50 persons × 6 m³/h = 300 m³/h

2. Air Changes per Hour (ACH)

ACH reflects how many times the air inside the shelter is completely replaced each hour. Multiply the shelter’s internal volume by the desired ACH. For private use, 2–6 ACH is recommended, with 1 ACH considered a minimum.

Example: Shelter volume: 200 m³ × 2 ACH = 400 m³/h

3. Leakage and Exhaust Compensation

To maintain positive pressure (typically 100–250 Pa)—which prevents contaminants from entering the shelter—you must account for leaks and exhaust airflow (e.g., through toilets, kitchens, airlocks). It's advisable to pressure-test the shelter pre-installation. If this data isn't available, include a 25% safety margin.

Example: Measured leakage + exhaust = 440 m³/h Add 25% margin = 550 m³/h

Step 3: Select the System

From the three calculations above, take the highest value—in this case, 550 m³/h—and select the next available system size that meets or exceeds it. For example, the Arconik ARC600, rated at 600 m³/h, would be appropriate.

Always opt for a buffer above your minimum requirements. Over time, aging seals, structural shifts, or external damage may increase leakage, especially after explosive events or long periods of disuse. Built-in redundancy is essential. A manual crank backup is critical to ensure functionality during power outages.

Why Choose Arconik CBRN Filtration Systems?

Arconik, a trusted global leader in CBRN filtration, produces over 10,000 systems and filters annually. Subject to frequent quality and procedural audits by governments and third parties, Arconik’s products are certified and recertified yearly, undergoing rigorous performance testing. With systems ranging from 36 m³/h to over 1,800 m³/h and fully custom setups for larger airflow requirements, Arconik offers tailored solutions for any shelter size.

In Australia, Hardened is the exclusive distributor of the Arconik CBRN filtration range. Contact us to learn more or order your system today.