Indoor Air Pollution Monitoring

Transcription

1 Indoor Air Pollution Monitoring Zohir Chowdhury, Ph.D. Environmental Health Graduate School of Public Health San Diego State University San Diego, CA, USA

2 What to Monitor 1. Particulate Matter 2.5 (PM 2.5 ) PM 2.5 : Eye, nose, throat and lung irritation, coughing, sneezing, runny nose and shortness of breath Pulmonary diseases (asthma and bronchitis) and heart diseases Infants and elderly people particularly sensitive 2. Carbon Monoxide (CO) CO has higher (X240) affinity to Hemoglobin than O 2 Headache, shortness of breath CO poisoning Death

3 Instrument Monitoring Choices PM 2.5 CO Pollutant Real-Time Integrated Instantaneous Real-Time Integrated Instantaneous Method Pump & Filter Passive Tubes Dust Trak UCB Dust Trak HOBO HOBO CO Grab Sample Casella Casella Side Pak Side Pak Grimm Grimm pdr pdr

4 Monitoring Equipment Available UCB Particle Monitor TSI DUSTTRAK Aerosol Monitor SKC PCXR8 Sample Pump with 37 mm filter & BGI cyclone HOBO CO Monitor Draeger CO Dosimeter Tube CO Bag Sample Casella TSI SidePak

5 Real-time PM 2.5 Concentrations with UCB Particle Monitor Particle Mass (mg-m -3 ) Particle Mass (mg-m -3 ) 300 Fine Particle Mass (PM 2.5 ) UCB Particle Monitor Breakfast preparation 48 hr mean = 4.4 mg/m 3 Peak ~ 250 mg/m 3 Lunch and dinner preparation /19 12:00 7/19 18:00 7/20 0:00 7/20 6:00 7/20 12:00 7/20 18:00 7/21 0:00 7/21 6:00 7/21 12:00 7/21 18:00 Sampling Time Note: Y-Axis Scales are different Open Fire Fine Particle Mass (PM 2.5 ) UCB Particle Monitor 48 hr mean = mg/m 3 Peak ~ 9 mg/m 3 0 6/21 6:00 6/21 12:00 6/21 18:00 6/22 0:00 6/22 6:00 6/22 12:00 6/22 18:00 6/23 0:00 6/23 6:00 6/23 12:00 6/23 18:00 Sampling Time Improved Stove

6 5:35 5:56 6:17 6:38 6:59 7:20 7:41 8:02 8:23 8:44 9:05 9:26 9:47 10:08 10:29 10:50 11:11 4:37 5:05 5:33 6:01 6:29 6:57 7:25 7:53 8:21 8:49 9:17 9:45 10:13 10:41 11:09 11:37 12:05 12:33 Real-Time CO Concentrations with HOBO Monitor Note that fire continues for much of day CO in ppm Peak~80 ppm CO Open Fire Stove CO in ppm Peak~10 ppm CO 2 0 Improved Stove

7 IAP Instrument Placement Ensure Monitors can sample surrounding air Source: Berkeley Air

8 Comparison of PM Measuring Instruments Source: Berkeley Air

9 Comparison of CO Measuring Instruments ~$10/tube Source: Berkeley Air

10 4 points to remember 1. IAP measurements necessary for validating effectiveness of improved stoves projects 2. Many IAP measurement options exist vary in cost and accuracy (tradeoffs) 3. Choice of method depends on context (purpose, capacity, finances) 4. All methods require data management & quality assurance/quality control plans Source: Berkeley Air

11 Training and Resources Available Online Resources o o PCIA Website: Vietnam Training South Africa Training UC Berkeley Website Berkeley Air/CEIHD Professor Kirk Smith Training: o o Berkeley Air San Diego State University

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13 EXTRA SLIDES

14 Shown on Next Slide heavy & bulky limited data (one average number) slow (weeks to obtain results) expensive (~$40 per datum, >$10k capital cost) 5/6-place analytical lab balance & controlled climate weighing room Self governing programmable pump Filter cassette Chargeable battery (battery charger not shown) Cyclone for size selection Petri dishes for transporting filters Airflow calibrator

15 Gravimetric Theory Mass filter BEFORE sampling Mass filter AFTER sampling Gained Mass = AFTER Mass BEFORE Mass Temperature & Relative Humidity Controlled Room Mettler Toledo MT-5 Electronic Microbalance: measures 1 g

16 Flow Calibration Devices Gilian Gilibrator BIOS Dry Cal Rotameter

17 Theory: TSI DustTrak PM Monitor Real-time Light scattering instrument Light from Laser scattered at 90 degree Photodetector measures scattered light in Voltage Unit which is proportional to PM concentrations

18 Theory: UCB Particle Monitor (Litton et al. 2002, 2004) Operates on principles of optical scattering by smoke particles Uses LED with an output wavelength of 880 nm and a photodiode that measures the intensity of scattered light at a 45 0 angle from forward direction Responds to PM 2.5 particles Temperature Sensor Data Logger

19 Theory: HOBO CO Monitor electrochemical sensor o converts CO gas to an electric signal 2 electrodes immersed in a highly conductive electrolyte solution (sulfuric acid) CO, in the presence of O 2, is converted to CO 2 voltage drop across resistor is measured using Ohm s law (V=IR) voltage related to CO concentration

20 Theory: CO Passive Diffusion Tube Diffusion tubes o Small (can be worn by participant) o Indicated by stain length in tube CO + Na 2 Pd(SO 3 ) 2 Pd + CO 2 + SO 2 + Na 2 SO 3 o Measures total exposure, not continuous Source: EPA. Air Quality Criteria for Carbon Monoxide. June, 2000.

21 Theory: CO Bag Sample

22 limitations to Berkeley Air kit HOBO CO logger (~$240/unit) o requires recalibration o Sensor degrades with time o lots of data CO dosimeter tube (~$10.00/tube) o imprecise o one-time use o expensive for large studies UCB particle monitor (~$500/unit) o requires zeroing at every use o needs careful cleaning o new technology (not traceable to national standards) o lots of data DustTrak Particle Monitor (~$6,500/unit) o Requires zeroing at every use o Needs to be calibrated to combustion sources Only the pump and filter method produce a physical sample

23 PM Concentrations ( g-m -3 ) Intra-household Variability Household PM Post Plancha Installation Measurement Rainy I 2003 Rainy II 2003 Dry Cold 2003 Dry Warm 2004 Rainy I 2004 Rainy II 2004 Dry Cold 2004