SASS 3100R Dry Filter Aerosol Sampler - resrchintl.com · SASS 3100/3100R• December, 2013 •...

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SASS 3100/3100R• December, 2013 • Page 1 SASS 3100R Dry Filter Aerosol Sampler

Transcript of SASS 3100R Dry Filter Aerosol Sampler - resrchintl.com · SASS 3100/3100R• December, 2013 •...

SASS 3100/3100R• December, 2013 • Page 1

SASS 3100R Dry Filter Aerosol Sampler

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Dry samplers have favorable properties: – Organisms maintain their original state; wet sampling

causes a fundamental change in environment – A dry collection strategy means no water needs to be

carried or stored; – Water freezing is not a concern- the operating

temperature range can be expanded; – Dry samplers tend to be simpler in design, more reliable

and more compact, longer running and more easily decontaminated.

However, collected materials must be extracted in a second step

SASS® 3100R Dry Sampler

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SASS 3100R Dry Air Sampler

Lightweight and portable- 2.8 kg w/bat. 24-hour operation on battery power Microprocessor in sampler allows either biological or radiological filter to be used over a range of sampling rates. Collection efficiency for biological filter:

- 0.5 µm dia: 50% - 1.0 µm dia: 75% - 2.0 µm >dia: 90%

Collection efficiency for radiological: >99% for >0.3 microns dia. Operable from -40C to 70C Programmable/digitally controllable SASS 3100 Top performer out of 10 competitors at 2008 TRE 08-2; top contender for U.S. JBTDS program.

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SASS® 3100R Electrical/Electronic Interfaces

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The biological electret filter is designed to optimize conversion of electrical energy to pressure-volume pneumatic energy

This maximizes sampled air volume and operating time on battery power- the 3100R sampler offers unusually high performance in a small long-running portable format.

SASS® 3100 System Optimization

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The 3100R sampler can be programmed from a PC to automatically perform multi-step protocols

Features that can be modified include: – Delay before sampling – Sampling time – Delay between sampling periods – Number of sampling periods. – Sampling flow rate

When downloaded to the sampler, it will execute the feature set on all future runs until the protocol is changed.

The sampler can also be turned on and off remotely by wireless or RS-232 commands

Software Modifiable Operation

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SASS 3100R Proprietary Filters

RI’s biological filter media has an extremely high efficiency coupled with a pressure drop that is 5% of a comparable conventional filter.

Both filter media are fibrous ‘electret’ materials – A complex electric field emanates from each

polypropylene filter fiber; – ‘Action-at-a-distance’ electrostatic attraction

draws aerosols to the fibers; – Electrostatic forces cause captured aerosols

to cling tightly to each filter’s fibrous matrix – Can withstand prolonged water immersion; – Stable for a decade or more; – Will withstand temperatures to 700C; – 43 mm nominal active diameter

Portable samplers based on these filters exceed all others in collection ability, small system size, temperature range and operating life

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The felt-like polypropylene electret material is mounted in a polypropylene frame using one of two placement methods: – Sonic welding; or – A friction-lock approach wherein the

filter “biscuit” is sandwiched between the frame and an annular backing scrim

The latter is convenient for forensic applications since the biscuit can be removed with tweezers for analysis.

The filter assembly is mounted onto the sampler by pressing and friction-locking it onto an inlet boss. There is no inlet ducting to become contaminated.

Contamination by previous test residues is minimized.

Filter Assemblies

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Comparable paper filters for radioactive aerosol collection have extremely high pressure drops and often need to be used with a vacuum pump to create an adequate air flow.

RI’s electrostatic filters coupled with the SASS 3100R blower provide an unprecedented range of field opportunities never before possible in the radioactive aerosol collection field: – 24 hour unattended operation – Remote control and programmability – Small size and quiet operation

Very low radiative self-absorption- 2.2 mg/cm2 mass/area is only 25% of the areal density of a Whatman 41 filter.

Of course, the filter is also useable for biological aerosols

Comments on the Radioactive Aerosol Filter

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The exceptionally strong electrostatic holding forces also provide a challenge if the particles need to be removed from the filter for analysis.

Research International has developed a small manual ‘extracting machine’ and a preferred extraction fluid formula to efficiently remove particulates.

Efficiencies of 60-80% are typical.

Alternatively, the biscuits will also fit many standard 50mm paper filter holders

Typical radioactive material assays do not require particulate extraction- measurements are made directly from the filter.

Extracting Particulates

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SASS 3010 Manual Particle Extractor

Extracts particulates from the electret filters used with SASS 3100R or SASS 4100;

A 4 to 10 ml charge of extraction fluid is added from a 16 ml dropper bottle

Sonic agitation dislodges particulates from the fibrous matrix

The extracted sample is discharged into the dropper bottle; use with HHA’s or any wet bioanalyzer

1 minute process time 60-80% efficiency Supported in DoD technology upgrade program

(JBTDS application) U.S. Patents 8,057,608 and 8,142,570

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Extraction Efficiency Vs. Extraction Fluid Volume

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Extraction efficiency is essentially constant as long as the fluid sample exceeds 4 ml

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The samplers are easy to service and decontaminate.

The volute surrounding the fan rotor is detachable by removing three finger screws. It can be directly immersed in bleach or other decontaminating solution.

The fan rotor may be bleach decontaminated by turning the unit upside down and immersing the rotor assembly in bleach. Turning the unit on after removal from the bleach will spin dry residual fluid on the rotor and minimize corrosion.

The entire rotor assembly can be replaced by removing 4 screws and disconnecting an electrical connector.

SASS® 3100R Decontamination

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Research International, Inc.

17161 Beaton Road SE Monroe, WA 98272-1034

Phone: 360-805-4930 • Toll Free: 1-800-927-7831 www.resrchintl.com • [email protected]