W31P4Q18Q0165_J&A(2)_090618.pdf

USATA-NG-0078-18

Attachment 06

SOLE SOURCE JUSTIFICATION

FOR TSI 3938NL56 SCANNING MOBILITY PARTICLE SIZER

1. Contracting Agency: US Department of the Army, AMCOM Contracting Center – Redstone, Building 5303, Attention: CCAM-ALH, Redstone Arsenal, Alabama 35898- 5280.

2. Description of Action: In accordance with Title 10 U.S.C. 2304(c)(1), as implemented by FAR 6.302-1(a)(2), only one responsible source and no other supplies or services will satisfy agency requirements, the , Redstone Arsenal, requests sole source commercial equipment supplied by TSI, Inc.

based on commercial catalog industry pricing at the total estimated price of for the purchase of a quantity of one (1) TSI 3938NL56 Scanning Mobility Particle Sizer inclusive of the required accessories and freight as follows:

3. Background: has a requirement is to procure a nanometer aerosol electrical mobility particle spectrometer that can measure aerosol electronic mobility spectra for particles with a lower cutoff point no larger than 3 nanometers (nm). Systems that can measure below 3 nm are acceptable. The system shall consist of the differential mobility analyzer (DMA) and associated electronics and hardware, a condensation particle counter (CPC), aerosol charge neutralizer, along with firmware and software that provides automated mobility spectrum measurements and mobility spectrum deconvolution to provide a particle size spectrum. This is required to measure nanometer sized particles generated through radiolysis of vapor molecules.

4. Justification: is the only vendor that can supply a system meeting the above requirements. provides interchangeable detectors resulting in at least two acceptable material solutions, the 3938NL56 and 3938E77 Scanning Mobility Particle Sizers. The 3938NL56 measures down to 2.5 nm, while the 3938E77 measures down to 1 nm with additional growth amplification hardware. The 3938NL56 is determined to be the best solution for the requirement described above, based on cost and complexity, since the 3938NL56 does not require the growth amplification hardware. Market research was conducted in April 2018 to consider similar items from Government, professional, and /or industry sources, and it was determined that multiple vendors could not meet the requirement to

Item Model AMOUNT USATA Site Scanning Mobility Particle Sizer PN:

3938NL56

APSL

Advanced Aerosol Neutralizer (Soft X-ray) (Advanced Aerosol Neutralizer Soft X-ray Gen 2

PN: 3008 APSL

Flowmeter, 20 L/min, Air only, ¼ inch

PN: 4148 APSL

Freight N/A APSL

USATA-NG-0078-18

Attachment 06 measure down to 2.5 nm. The only vendor capable of supplying this measuring requirement is

Contracting Officer Certification: I certify that this justification is accurate and complete to the best of my knowledge.