2003 Progress Report: Development of the “Leland Legacy” Air Sampling Pump

EPA Grant Number: R828678C007
Subproject: this is subproject number 007 , established and managed by the Center Director under grant R824834
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).

Center: Mickey Leland National Urban Air Toxics Research Center (NUATRC)
Center Director: Beskid, Craig
Title: Development of the “Leland Legacy” Air Sampling Pump
Investigators: Hall, Peter
Institution: SKC Inc.
EPA Project Officer: Chung, Serena
Project Period: January 2, 2001 through December 31, 2005 (Extended to December 31, 2008)
Project Period Covered by this Report: January 2, 2003 through December 31, 2004
RFA: Mickey Leland National Urban Air Toxics Research Center (NUATRC) (1997) RFA Text |  Recipients Lists
Research Category: Air Quality and Air Toxics , Targeted Research

Objective:

The purpose of this project was to develop a personal air-sampling pump with the following specifications: (1) the pump would draw 10 liters of air per minute against a pressure drop of 12 inches of water, operating continuously for 24 hours from a rechargeable battery pack; (2) the design would be optimized for quiet operation and low power with a low noise level; (3) the pump would contain sophisticated control and data logging capabilities; and (4) this device would be lightweight, user-friendly, and compatible with the Sioutas personal cascade impactor sampler (PCIS).

Progress Summary:

This project was developed in response to RFP 2000-01 “Development of a High Efficiency Pump for the Personal Particulate Matter Monitor.” The project is in compliance with appropriate quality control and quality assurance procedures as per guidelines of the Mickey Leland National Urban Air Toxics Research Center (NUATRC) and the U.S. Environmental Protection Agency (EPA). This was a one-year project October 2000-October 2001. The project was granted a no-cost extension through December 2003.

The study developed a pump called the ‘Leland Legacy Pump.’ It uses an SKC patented flow control system (Patent No. 5,892,160) used successfully on other SKC sampling pumps. It is a “Closed loop” system where the air drawn through the pump passes through a measurement tube situated in the exhaust. The resulting pressure drop across the tube is monitored and compared to a calibration stored in the pump memory. The pump is a dual diaphragm pump in which rotational energy from a small DC motor is converted to linear motion by a shaft mounted eccentric bearing and connecting rod assembly, to drive the two pumping diaphragms. The diaphragms are molded from a rubberized material and operate with a rolling motion rather than stretching to minimize power requirements. Each pumping chamber contains inlet and exhaust valves, which respond to the pressure changes in the pump chambers during the pump stroke and require no physical actuation. The design of the valves is such as to minimize the pressure required for opening and closing, hence the power requirements, as well as to reduce noise. Both the inlet and exhaust paths of the pump mechanism utilize dampener chambers to reduce pulsation in the airflow caused by the cyclic nature of the pump operation. The rigid sections of the pump are injection-molded from thermoplastic material to providing strength and light weight.

The pump stack design ensures simple mechanical assembly with self-aligning parts and clips. The printed circuit board screws in/out without soldering. With only 2 screws in the entire pump stack, there is easy maintenance and repair. Pumping area and motor eccentric were optimized to reduce the power requirement. This improved the efficiency of the pump and helped to achieve the design specification of a 24-hour run time.

The battery pack of the pump uses 10 Li-ion rechargeable cells arranged in a series/parallel arrangement to give a nominal voltage of 7.2 V with a capacity of 9 A-hr. The battery pack is made to be removable from the pump case to allow quick replacement of a discharged pack if time is not available for recharging on the pump. The pump case is molded using a two-shot process that allows the body to be molded in hard plastic with an over-molding of a softer material in certain sections. The softer rubber-like material is used to form a buffer around the edges of the case to protect against damage as well as help with noise reduction. The pump case includes a large LCD, large buttons for keypad operation, a running LED, and a replaceable filter on the inlet. The pump is also equipped with a microprocessor that has a 256 K non-volatile memory, which enables data storage within the personal pump. The microprocessor makes corrections for temperature and atmospheric pressure changes allowing the pump to be calibrated in terms of volumetric flow as required for operation with the PCIS. Capitalizing on SKC’s previous developments, an optional Datatrac software system was designed for programming and recordkeeping. An SKC-patented Calchek® feature (Patent No. 6,227,031) was added for direct communication to a primary standard for flow calibration.

The Leland Legacy Pump meets the following specifications:

  • Flow range: 5 to 15 Lpm;
  • Accuracy: +/- 3% of setpoint after calibration to desired flow rate
  • Compensation: 10 Lpm at 12” H2O, 15 Lpm at 5” H2O, 5 Lpm at 25” H2O;
  • Flow fault: If flow drops by > 5%, pump stops; attempts to restart 10 times;
  • Noise levels: 55 db in noise reducing pouch at 10 Lpm and 12” H2O;
  • Ruggedness: impact, water, and dust resistant;
  • Run time and battery features: 24 hours at 10 Lpm and 12” H2O backpressure, 7.2 V, 10 A-hr capacity, input voltage 100-240 V AC. Full recharge time is 15 hours. It can run continuously from line voltage using the pump charger.

The compatibility of the Sioutas sampler and the Leland Legacy Pump was tested by operating the sampler in conjunction with the SKC pump for a 24-hour period. The test run indicated a battery run time of 5-hours maximum. The pump was therefore run with battery + AC adapter to accomplish a 24-hour run time. In order to achieve a 24-hour run time, a higher capacity battery pack has been ordered, due to the higher than expected backpressure of the Sioutas sampler. This has resulted in a delay in completion of the final report. A Draft Final Report is expected in February 2004.

The SKC’s “Leland Legacy Pump” is commercially available on the website: http://www.skcinc.com/pumps.asp Exit .

Future Activities:

  • Submission of a Draft Final Report.
  • External peer and internal review of the report.
  • Publication of the report.


Journal Articles on this Report : 1 Displayed | Download in RIS Format

Other subproject views: All 2 publications 2 publications in selected types All 1 journal articles
Other center views: All 144 publications 62 publications in selected types All 53 journal articles
Type Citation Sub Project Document Sources
Journal Article Misra C, Singh M, Shen S, Sioutas C, Hall PM. Development and evaluation of a personal cascade impactor sampler (PCIS). Journal of Aerosol Science 2002;33(7):1027-1047. R828678C007 (2001)
R828678C007 (2002)
R828678C007 (2003)
R828678C007 (2004)
R828678C007 (Final)
R828678C009 (2003)
R828678C009 (Final)
R827352 (2004)
R827352 (Final)
R827352C014 (Final)
  • Full-text: ScienceDirect-Full Text HTML
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  • Abstract: ScienceDirect-Abstract
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  • Other: ScienceDirect-Full Text PDF
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  • Supplemental Keywords:

    RFA, Health, Scientific Discipline, PHYSICAL ASPECTS, Air, ENVIRONMENTAL MANAGEMENT, POLLUTANTS/TOXICS, Air Pollution, particulate matter, air toxics, Health Risk Assessment, Chemicals, Air Pollution Effects, Risk Assessments, Biochemistry, Environmental Monitoring, Physical Processes, Engineering, Chemistry, & Physics, Risk Assessment, health effects, urban air, urban air quality, air pollutants, epidemiology, human health effects, atmospheric particles, aerosol particles, exposure, air sampling pump, chemical composition, air sampling, chemical detection techniques, human exposure, environmental contaminants, lung inflamation, particulate exposure, personal cascade impactor sampler, urban air pollution, Volatile Organic Compounds (VOCs), human health, cardiovascular disease, exposure assessment, human health risk, biomarker

    Relevant Websites:

    http://www.sph.uth.tmc.edu/mleland/ Exit
    http://www.skcinc.com/pumps.asp Exit

    Progress and Final Reports:

    Original Abstract
  • 2001 Progress Report
  • 2002 Progress Report
  • 2004 Progress Report
  • 2005
  • 2006
  • 2007
  • Final Report

  • Main Center Abstract and Reports:

    R824834    Mickey Leland National Urban Air Toxics Research Center (NUATRC)

    Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
    R824834C001 Air Toxics Exposures Among Teenagers in New York City and Los Angeles - A Columbia-Harvard Study (TEACH)
    R824834C002 Cardiopulmonary Response to Particulate Exposure
    R824834C003 VOC Exposure in an Industry Impacted Community
    R824834C004 A Study of Personal Exposure to Air Toxics Among a Subset of the Residential U.S. Population (VOC Project)
    R824834C005 Methods Development Project for a Study of Personal Exposures to Toxic Air Pollutants
    R824834C006 Relationship Between Indoor, Outdoor and Personal Air (RIOPA)
    R824834C007 Development of the "Leland Legacy" Air Sampling Pump
    R824834C008 Source Apportionment of Indoor Polycyclic Aromatic Hydrocarbons (PAHs) in Urban Residences
    R824834C009 Development of a Personal Cascade Impactor Sampler (PCIS)
    R824834C010 Testing the Metals Hypothesis in Spokane
    R828678C001 Air Toxics Exposures Among Teenagers in New York City and Los Angeles—A Columbia-Harvard Study (TEACH)
    R828678C002 Cardiopulmonary Effects of Metal-Containing Particulate Exposure
    R828678C003 VOC Exposure in an Industry Impacted Community
    R828678C004 A Study of Personal Exposure to Air Toxics Among a Subset of the Residential U.S. Population (VOC Project)
    R828678C005 Oxygenated Urban Air Toxics and Asthma Variability in Middle School Children: A Panel Study (ATAC–Air Toxics and Asthma in Children)
    R828678C006 Relationship between Indoor, Outdoor and Personal Air (RIOPA). Part II: Analyses of Concentrations of Particulate Matter Species
    R828678C007 Development of the “Leland Legacy” Air Sampling Pump
    R828678C008 Source Apportionment of Indoor PAHs in Urban Residences 98-03B
    R828678C009 Development of a Personal Cascade Impactor Sampler (PCIS)
    R828678C010 Testing the Metals Hypothesis in Spokane
    R828678C011 A Pilot Geospatial Analysis of Exposure to Air Pollutants (with Special Attention to Air Toxics) and Hospital Admissions in Harris County, Texas
    R828678C012 Impact of Exposure to Urban Air Toxics on Asthma Utilization for the Pediatric Medicaid Population in Dearborn, Michigan
    R828678C013 Field Validation of the Sioutas Sampler and Leland Legacy Pump – Joint Project with EPA’s Environmental Technology Validation Program (ETV)
    R828678C014 Performance Evaluation of the 3M Charcoal Vapor Monitor for Monitor Low Ambient Concentrations of VOCs
    R828678C015 RIOPA Database Development
    R828678C016 Contributions of Outdoor PM Sources to Indoor and Personal Exposures: Analysis of PM Species Concentrations” Focused on the PM Speciation and Apportioning of Sources
    R828678C017 The Short and Long-Term Respiratory Effects of Exposure to PAHs from Traffic in a Cohort of Asthmatic Children