Aspect analyser for Biodetection System

The Aspect analyser / non-specific biodetector is used for monitoring bioaerosol levels and uses ASAS (Aerosol Size And Shape) technology to simultaneously measure the size and shape of single aerosol particles in real time. The shape feature is especially useful in discriminating between battlefield man made interferents such as smokes and diesel oils.

The Aspect ASAS technology has been in service with the UK MOD as the non-specific bio detector in the PBDS (Prototype Biological Detection System) since the early 1990's and the upgraded version is a key element of the follow on IBDS (Integrated Biological Detection System).

The Aspect biodetector has been adopted as the non-specific trigger bio detector for the Japanese Defence Agency mobile CBRN Reconnaissance vehicles.

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SHAPE MEASUREMENTS

Many particle characterisation instruments measure only particle size and base their measurements on the assumption that the particles are perfect spheres. Both natural and man-made particles have a very wide variety of shapes and this can be a powerful parameter in classifying them. The Aspect biodetector uses Biral’s ASAS technology to simultaneously measure the size and shape of single particles at a high output rate.

In a compact, flexible mechanical design with easy to use software, the Aspect is a very powerful tool for a broad range of applications including biodetection and the monitoring of bioaerosol levels.

KEY FEATURES

A key feature of the Aspect is its high sensitivity which enables subtle changes in aerosol population to be detected. This is particularly useful for:

• Identifying subtle differences between aerosol or powder samples. Even when particle populations have continuous size and shape distributions, Aspect has the sensitivity to spot very small changes in size and shape characteristics.

• Discriminating particle types within aerosol or powder mixtures.  Aspect can discriminate discrete particle classes within a mixture by characterising particle shape. As a result, separate size or shape distributions can be generated and the ratio of particle species can be calculated.

PRINCIPLE OF OPERATION

ASAS Technology is at the core of Aspect operation. Developed jointly with the University of Hertfordshire and Dstl Porton Down in the UK, ASAS is an optoelectronic technology using elastic scattering of laser light to determine particle size, shape and concentration. Scattered light is detected by four photomultiplier tubes (PMTs), three of which provide information on shape in terms of the light scattering profile which defines the particle asymmetry factor Af. A spherical particle is by definition symmetrical about all axes passing through its centre and is assigned an Af of zero. An infinitely long fibre is assigned an Af of 100. All four PMTs contribute information on the particle size.

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Contact Biral for more information

To find out more about this instrument or to discuss your application requirements please do not hesitate to contact Biral.

• wwwparticle@biral.com (or click the Make Request button below the product photograph)
• telephone to 01275 847787 (from the UK) or +44 1275 847787 (International)

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After Sales Support

Biral offers free advice and technical support for the lifetime of the instruments we sell. Once you have purchased the unit you can contact us for help:

• wwwaerosolsupport@biral.com
• telephone to 01275 847787 (from the UK) or +44 1275 847787 (International)

Product Information

• aspect_aerosol_size_and_shape_sensor_specification.pdf
• aerosol_brochure.pdf

Scientific Papers and Articles

• SPIE poster.pdf
• Using Light to Detect.pdf
• Shedding light on biodetection.pdf
• Microbiological aerosols.pdf