CBRN Air Filtration SystemsThe purpose of a CBRN air filtration system is to provide the occupants of vehicles or shelters with a supply of fresh ambient air free from Chemical, Biological, Radiological and Nuclear (CBRN) contaminants.

Gallay have used the latest technology to design and develop a modular CBRN

filtration system complying with the NATO AEP54 standard.

The modular approach provides an extremely compact and efficient system and

enables rapid design of bespoke systems to match specific customer vehicle requirements.

• Ambient air is drawn into the filtration system by a high efficiency brushless motor and blower assembly.

• The air passes through an inertial particle separator (IPS) removing the majority of particulates. The separated dust and debris is ejected from the IPS with a brushless scavenge blower.

• The air then passes into the filter cannister and through the HEPA filter to remove particulate threats.

• If a CBRN filter is fitted, the air then passes through a specially impregnated carbon section to remove nuclear / chemical vapour and gaseous threats.

• The clean air then passes from the filtration system into the crew compartment. A pressure relief valve (PRV) on the vehicle hull supports operating with a crew compartment over-pressure to the AEP54 requirement.

• The filtration system is controlled and monitored by a micro-processor ECU.

• Typical system weight including NATO number 1 training filter is 35kg.

CBRN Air Filtration System Operation

CBRN System air flow

Typical CBRN Filtration System

1. Inertial Particle Separator with integrated dust scavenge fan

2. Airflow meter

3. CBRN or training filter

4. Blower assembly

5. Electronic control unit (ECU)

6. Remote mounted user interface

7. Pressure Relief Valve (PRV)

Alternative System's

Typical reduced length Filter configuration

Effective canister length is 50% of

Standard NATO No. 1 Filter

Main Components

2. Airflow meter• The system airflow is measured and compared to

the target programmed into the ECU to ensure the

specified quantity of air is delivered despite changing operating conditions and filter restriction.

• Different volumetric airflows can be specified for ventilation (HEPA only filter) and fully protected (CBRN filter) modes.

1. Inertial Particle Separator pre-filter• Up to 96% design efficiency (ISO 5011 coarse dust).• The separated dust is ejected out of the system

with an integrated electric scavenge fan.• Brushless DC motor.

• Hardened stainless steel impeller

Main Components3. Filter

• Training and CBRN variants of the NATO number 1 Mk 2 filter are available.

• All filters incorporate a HEPA element better

than 99.997% efficient (BS3928 sodium flame test).

• The CBRN filter is compliant with NATO AEP54 edition 2 (Oct 2014) at 170 m3 / hour.

• Optional removable / replaceable HEPA

element gives logistics and life cycle cost benefits.

• Alternative CBRN filter cannister lengths are

available to suit higher or lower air flow rates.

• A ‘low pressure drop’ HEPA cannister is

available for high ventilation air flow applications.

4. High Pressure Blower• Bespoke 1kW brushless motor.• Air flow up to 240 m3/hour (with a suitable filter)

and AEP54 crew compartment over-pressure in a 55 degree C ambient.

• Hard anodized cast aluminium volute.• CNC machined aluminium impeller.

5. ECU• Micro processor ECU controls and monitors the

filtration system.

• Crew compartment over-pressure and filter blockage monitored and reported.

• Fault diagnosis and Diagnostic Trouble Code (DTC) reporting.

• Optional communication with vehicle systems

over CAN.• The airflow from the system can be varied in

different modes or with respect to vehicle speed.

Main Components

Main Components6. Remote user interface

• Bespoke CNC machined aluminium casing.

• Mode switch to start the system and change between operating modes.

• Status LEDs for the crew compartment over-pressure and filter blockage.

• Audible alarm with mute toggle switch.

• Malfunction indicator LED to display DTC’s.

• LED intensity automatically varies with changing ambient light.

• CAN bus communication with the filtration system ECU.

7. Pressure Relief Valve.

• The crew compartment over-pressure is supported by an adjustable pressure relief valve (PRV) mounted on the hull.

CBRN Filtration System TestingGallay CBRN filtration systems have completed the following tests to Military Standard 810:

• High temperature operating Method 501,.5, procedure ii, table 501.5-ii

• High temperature storage Method 501.5-I, procedure I, table 501.5-iii (induced condition).

• Low temperature operating, method 502.5, procedure ii.

• Low temperature storage, method 502.5 procedure i.

• Humidity to method 507.5, procedure ii, figure 507.5-7, table 507.5-ix.

• Salt fog to method 509.5.

• Vibration to method 514.6, table 514.6C-vi, composite wheeled vehicle.

• Shock to method 516.6, procedure I, figure 516.6-10.

• Vibration to method 514.4, Cat 8, Procedure I, table 514.4A-xvi, tracked profile.

• Vibration to method 514.7, cat 4, table 514.7C-v, composite wheeled vehicle.

A low cost HEPA filtration system is also available from Gallay for applications where a full CBRN filtration system is not necessary.

Gallay CBRN Filtration System

Applications

CBRN SYSTEM - VEHICLE CAPABILITY TESTING

• The CBRN system has the function to over pressurize the vehicle cabin to prevent

harmful media entering the cabin during a CBRN threat.

• For the CBRN system to gain the required vehicle over pressure requirements the cabin has to conform to certain equivalent

hole size leakage test figures to guarantee the sealing level which will allow the system

to reach the stated over pressures.

• To achieve this a vehicle leakage tester is

required to measure the rate at which the air is lost from the cabin areas when under a set pressure.