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Thoracic PPIs — Reusable

Orderable Items SKC Thoracic Parallel Particle Impactor (PPI®) Samplers are similar to traditional 37-mm filter cassettes in that they collect dust on standard 37-mm filters. That’s where the similarity ends! The impaction-based PPI Samplers are designed to provide a precise match to the ISO 7708/CEN criteria in a unique way.

  • Collection efficiency precisely matches ISO 7708/CEN size-selection criteria

  • Operate at 2 L/min for optimal sampling of metalworking fluids by NIOSH Method 5524 and thoracic TLV sampling of cotton dust or hard metals containing cobalt (Co) and tungsten carbide as Co

  • Conductive aluminum

  • Disposable PPI models are available





Performance Profile

Sampling Rate 2 L/min
Sample Pump AirChek Series
Sample Time Dependent on method used
Sample Media

37-mm, Quartz filter or 37-mm, 2.0-µm PTFE filter (NIOSH 5524) or 37-mm, 0.8-µm MCE filter

Back pressure on PTFE filters can vary within the same lot.

Tubing 1/4-in ID
Impaction Substrate Four 3/8-in diameter pre-oiled porous plastic discs
Analysis Gravimetric or chemical
Dimensions Height: (clip to exhaust): 4.25 in (10.8 cm)
Diameter: 1.8 in (4.6 cm)
Depth: 1.2 in (3.0 cm)
Weight 3.3 oz (93.6 gm)





How PPI Works

The patented* SKC Parallel Particle Impactor (PPI) Sampler operates with four small impactors in the inlet section of the device. Each impactor features a unique 50% cut-point to target a specific one-quarter segment of the ISO 7708 curve resulting in a precise fit along the entire curve. A sample pump pulls air through the inlet nozzle of each impactor in the inlet plate. Particles larger than each impactor’s 50% cut-point are scrubbed and retained on the porous oiled impaction substrate, while smaller particles continue to the standard 37-mm collection filter for analysis.

* U.S. Patent No. 7,073,402

exploded diagram of PPI

SKC PPI Performance

SKC PPI models were evaluated side by side with other size-selective samplers. Potassium sodium tartrate (PST), dioctyl phthalate (DP), glass spheres (GS), and coal mine dust were used as test aerosol. A load of approximately 6.8 mg of coal mine dust on the PPI substrates did not adversely affect PPI performance.


Collection efficiency of the 2 L/min thoracic PPI Sampler

Collection efficiency of the 2 L/min thoracic PPI Sampler
compared to the ISO thoracic convention
(Click to enlarge)


Comparison of penetration characteristics measured for the thoracic PPI

Comparison of penetration characteristics measured for the thoracic PPI
Sampler, PEM 10 Sampler, and GK2.69 Cyclone using PST test particles
(Click to enlarge)


Trakumas, S., Salter, E., "Parallel Particle Impactor - Novel Size-selective Particle Sampler for Accurate Fractioning of Inhalable Particles," Journal of Physics: Conference Series 151 (2009), 012060

The link in the reference above is an author-created, non-copyrighted version of an article accepted for publication in the Journal of Physics: Conference Series 151. IOP Publishing Ltd. Is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. Go to http://dx.doi.org and enter doi: 10.1088/1742-6596/151/1/012060 for the definitive publisher authenticated version.

ISO/CEN 7708:1995 (2008), Air Quality — Particle Size Fraction Definitions for Health-related Sampling, search on 7708


SKC Limited Warranty and Return Policy

SKC products are subject to the SKC Limited Warranty and Return Policy, which provides SKC’s sole liability and the buyer’s exclusive remedy. To view the complete SKC Limited Warranty and Return Policy, go to the SKC Limited Warranty for Products and Return Policy page.