Component Repair and Calibration

Notice of Intent
The Centers for Disease Control and Prevention intends to award a sole source firm fixed price
purchase order to TSI Incorporated 500 Cardigan Road Shoreview, MN 55126 (CAGE Code:
24575) for the purchase of repair and calibration services for Government owned equipment.
Only the manufacturer (TSI Inc.) can repair and calibrate the Aerodynamic Particle Sizer because
proprietary models must be adjusted for the calibration, proprietary knowledge of internal flow
regulators is needed for the repair, and unique access to instrument components that are located
behind embedded electronics is required. Alternative service providers are not available because
proprietary information on the instrument operating model and flow regulation system is
required.
Description
TCI shall repair and calibrate 3 Aerodynamic Particle Sizers with an expected turnaround of 21
days. Upon receipt of instruments, TSI Inc. shall bring the 3 Aerodynamic Particle Sizers to a
calibration flow rate of 5 liters per minute (lpm) (1 lpm for sample + 4 lpm for sheath) and
maintain the calibration flow rate, even with a pressure drop of up to 50 inH20 at the inlet by
adjusting microprocessor controlled volumetric flow control, barometric pressure correction, and
separate pumps for sheath and total flows, to enable the Aerodynamic Particle Sizers to operate
under a wide range of conditions and still maintain calibration.
TSI Inc. shall also calibrate the 3 Aerodynamic Particle sizers for precise and accurate numbersize
distributions for 0.37 to 20 micrometers aerodynamic diameter using a time-of-flight
technique, and a patented, double-crest optical system to detect the occurrence of particle
coincidence (when more than one particle is in the detection area) and to identify poor signals
near the instrument’s lower detection threshold. The Government will provide the following
components for repair and calibration:

1.  Aerodynamic Particle Sizer-S/N 1169

2. Aerodynamic Particle Sizer-S/N 1203

3.  Aerodynamic Particle Sizer-S/N 72321006