Hong Kong Institute of Qualified Environmental Professionals Limited …hkiqep.org/wp-content/uploads/2015/11/HKIQEP_Air_with... · 2016-07-14 · Title: Hong Kong Institute of Qualified

Copyright@2016 Hong Kong Institute of Qualified Environmental Professionals Limited. All Rights Reserved.

AIRBy Ir. SW Pang


Syllabus1. Nature of Atmospheric Pollution (15%)

a. Physical structure & composition of the troposphere & stratosphere

Temperature, pressure, density, spatial and temporal relationships

Radiation

Odourb. Natural composition of the atmosphere (gases, particulates, aerosols,

moisture)

Typical concentrations of common species in the natural

background

Typical concentrations of common pollutants in polluted environments

c. Air pollutants

Definitions & characteristics (physical and chemical)

Particulates

Gaseous pollutants Toxic air pollutants

Threshold and non-threshold pollutants

Radionuclides, biological contaminants


Syllabus1. Nature of Atmospheric Pollution (Cont’d)

d. Physical and chemical pollutant processes

Transport, dispersion, dilution, transformation, scavenging

and atmospheric lifetimes.

Meteorological effects: influence of solar radiation and wind fields, lapse rate and stability conditions

Spatial and temporal variation of air pollutant concentrations

e. Local, regional and global air pollution

Long range transportation

Acid rain Photochemical air pollution

Global scale pollutants (greenhouse gases and climate

change; stratospheric ozone depletion and ozone depleting

substances; persistent organic pollutants)

f. Indoor air pollution


Syllabus2. Air Pollution Sources and Impacts (18%)

a. Anthropogenic sources of air pollution

Stationary

Mobile

Fugitive and non-fugitiveb. Natural sources of air pollution

Volcanoes, wild fires, earthquakes, etc.

c. Receptors (human, animal, plant, materials, atmospheric processes)

d. Source/Receptor relationships (spatial and temporal)

e. Adverse effects Health effects (mortality, morbidity, respiratory illness, sub-clinical

effects)

Ecological impacts, vegetation and forest deterioration,

Materials corrosion,

Lake acidification Others

f. Health impact assessments, economic impact assessments, air

toxics and risk assessments (e.g., cancer burden, acute, chronic)


Syllabus3. Air Pollution Modelling (15%)

a. Purposes of for air pollution modelling (Environmental Impact

Analysis, plant siting, emergency response planning, accidental

release, public relations, economic impacts)

b. Modelling level of effort (screening, planning, compliance)c. Types of air pollution models

Box, Gaussian Dispersion

Photochemical,

Physical, numerical,

Receptor models d. Emission inventory and emission modelling

e. Model limitations, assumptions, accuracy

f. Source / Receptor relationships

g. Air quality forecasting


Syllabus4. Air Quality Management Strategies (14%)

a. Air pollution prevention versus control

b. Best practicable means / best available control technology,

technology forcing approach

c. Air quality standards approach and criteria pollutantsd. Application of emission trading, emission offsetting and other

market-based mechanism on air quality management

e. Socio-economic and political issues, polluter pays principle, cost-

benefit approach

f. Regulatory and non-regulatory approachesg. Air quality and emission limits, air pollutant nuisance, prevention of

significant deterioration

h. Dissemination of air quality information; air quality index/air quality

health index

i. Education and public awareness of air pollution


Syllabus5. Air Pollution Control Technology (18%)

a. Control of emissions from stationary sources

b. Control of emissions from mobile sources, including vehicles,

automotive, vessels, aircrafts

c. Control of gaseous pollutants Absorption, adsorption, condensation, incineration

Advances of gaseous pollutant control technologies

d. Control of particulate pollutants

Cyclone and inertial separators, wet scrubbers, electrostatic

precipitators and baghouses Advances of particulate pollutant control technologies

e. Combustion control, fuel restriction and control, material restriction

and control

f. Management and disposal of waste streams (multimedia)

g. Emission factors and estimatesh. Compliance planning; limits, standards, technology, and

documentation


Syllabus6. Ambient Air and Emission Sampling and Analysis (20%)

a. Site selection required for effective and representative sampling

b. Health and safety precautions

c. Meteorological monitoring

d. Isokinetic versus constant rate versus proportional samplinge. Effects of particle size on sampling accuracy.

f. Optical remote sensing

g. Continuous emission monitoring (CEMs)

h. Instrumentation and data acquisition systems

i. Real-time monitoring versus intermittent discreet sampling/analysisj. Reference methods


Suggested Reading Materials• Thad Godish, Wayne T. Davis, Joshua S. Fu, Air Quality, 5th ed., CRC Press, 2015

• Richard C. Flagan and John H. Seinfeld, Fundamentals of Air Pollution Engineering, Dover Publications, Inc., 2012

• Noel De Nevers, Air Pollution Control Engineering, 2nd ed., Waveland Pr Inc., 2010

• Environmental Protection Department, HKSAR (Air quality related webpages)

http://www.epd.gov.hk/epd/english/environmentinhk/air/air_maincontent.html

• A Clean Air Plan for Hong Kong, Environment Bureau, HKSAR

http://www.enb.gov.hk/sites/default/files/New_Air_Plan_en.pdf

• European Commission - Environment (Air quality related webpages)

http://ec.europa.eu/environment/air/index_en.htm

• US Environmental Protection Agency (Air quality related webpages)

https://www.epa.gov/learn-issues/learn-about-air

https://www.epa.gov/science-and-technology/air-science

• US Environmental Protection Agency (Air Pollution Training Institute)

http://www.apti-learn.net/LMS/EPAHomePage.aspx

• World Health Organization (Air webpages)

http://who.int/phe/health_topics/outdoorair/en/

• Recommended Study Materials, Text Books & Resources of Qualified Environmental Professional (QEP) Certification, The Institute of Professional Environmental Practice

http://www.epd.gov.hk/epd/english/environmentinhk/air/air_maincontent.html

http://www.enb.gov.hk/sites/default/files/New_Air_Plan_en.pdf

http://ec.europa.eu/environment/air/index_en.htm

https://www.epa.gov/learn-issues/learn-about-air

https://www.epa.gov/science-and-technology/air-science

http://www.apti-learn.net/LMS/EPAHomePage.aspx

http://who.int/phe/health_topics/outdoorair/en/


Sample Questions1. Nature of Atmospheric Pollution (15%)

• Which of the following is true about nitric oxide?

(a) A precursor of photochemical smog; (b) reacts readily with ozone to produce nitrogen dioxide; (c) Released through the combustion of fossil fuels; (d) All of the above; (e) None of the above

• Which following pollutant degrades visibility?

(a) CO; (b) CO2; (c ) N2O; (d) NO; (e) PM2.5

• Which of the following indoor air pollutants is a threshold air pollutant?

(a) Benzene; (b) fine suspended particulates; (c) Carbon monoxide; (d) Polycyclic aromatic hydrocarbon; (e) Radon


Sample Questions2. Air Pollution Sources and Impacts (18%)

• Which of the following is a major source of VOC emissions?

(a) Power generation; (b) Cement manufacturing; (c) Rock crushing; (d) Petrol refueling; (e) Coal mining

• Which of the following is most likely the disease associated with the exposure to elevated CO levels in the air?

(a)Lung cancer; (b) Acute lower respiratory diseases; (c) Damage to digestive system; (d) Eye irritation; (e) Cardiovascular diseases

• Which of the following air pollutants is associated with the highest long-term health risk to the public?

(a) Carbon monoxide; (b) Ozone; (c) Fine suspended particulates (PM2.5); (d) Sulphur dioxide; (e) Nitrogen dioxide


Sample Questions3. Air Pollution Modelling (15%)

• Which of the following can ONLY be achieved by emission-based air quality models?

(a) Understanding the cause of a past air pollution episode; (b) Estimate the relative contributions of pollution from different sources; (c ) Prediction of tomorrow's air quality; (d) Estimation of ambient pollutant concentration under different air control options; (e) All of the above

• What is the calculated change for required resources when the horizontal grid resolution of a meteorological model is changed from 2km to 1km?

(a) Increase by a factor of two; (b) Decrease by a factor of two; (c ) Increase by a factor of four; (d) Decrease by a factor of four; (e) Increase by a factor of eight


Sample Questions

3. Air Pollution Modelling (Cont’d)

• Which of the following is/are true for Gaussian dispersion models:

(a) they assume pollutant concentrations are normally distributed in a bell-shaped curve about the plume; (b) they are limited to predicting concentrations within 50 km from the sources; (c) Source emission strengths are assumed to be constant; (d) All of the above; (e) None of the above


Sample Questions

4. Air Quality Management Strategies (14%)

• Which of the following is an example of the “Command and Control" approach to air quality management?

(a) Pollution charges; (b) Emission trading; (c) Environmental impact assessment; (d) Emission standards; (e) None of the above

• Which of the following strategies is NOT used in controlling emission from motor vehicles in Hong Kong?

(a) Emission standards; (b) Fuel restriction; (c) Retrofitting of emission devices; (d) Traffic management; (e) Emission trading


Sample Questions

4. Air Quality Management Strategies (Cont’d)

• Which of the following true for the Air Quality Health Index (AQHI) being reported by Hong Kong EPD?

(a) AQHI serves as a measure of the effectiveness of the air quality management programmes; (b) AQHI is calculated by comparing the air pollutant concentrations with the respective Air Quality Objectives of Hong Kong; (c) AQHI is reported on an hourly basis; (d) AQHI is reported as a figure between 0 and 500; (e) When AQHI reaches “high” or above, all people should reduce physical exertion


Sample Questions

5. Air Pollution Control Technology (18%)

• Which of the following control equipment has the LEAST emission reduction performance in controlling volatile organic compound (VOC) emissions from a solvent process?

(a) Catalytic incineration; (b) Bag filter; (c) Thermal incineration; (d) Activated carbon adsorber; (e) Condensation

• What is the purpose of Hong Kong Government’s subsidizing the replacement of catalytic converters and oxygen sensors of LPG taxis and light buses?

To ensure proper reduction of:

(a) NOx and CO emissions; (b) NOx and SO2 emissions; (c) CO and CO2 emissions; (d) NOx and particulate emissions; (e) SO2 and hydrocarbons emissions


Sample Questions

5. Air Pollution Control Technology (Cont’d)

• Which of the following is/are true with respect to a pulse-jet baghouse?

(a) Collected dust is cleaned by injecting a blast of high pressure air; (b) Collected dust is removed from outside of the bag during bag cleaning; (c) The flow of dirty air into the compartment does not stop when the bags are cleaned; (d) All of the above; (e) None of the above


Sample Questions

6. Ambient Air and Emission Sampling and Analysis (20%)

• Which of the following is/are the factors to be taken into account in the establishment of an urban air quality monitoring network?

(a) Spatial representativeness; (b) Population distribution; (c) Land use; (d) All of the above; (e) None of the above

• In addition to ozone, which of the following air pollutants should at least be monitored to facilitate better understanding of photochemical air pollution?

(a) NOx and O2; (b) NOx and volatile organic compounds; (c) CO and volatile organic compounds; (d) CO and particulate matter; (e) O2

and particulate matter


Sample Questions

6. Ambient Air and Emission Sampling and Analysis (Cont’d)

• In conducting the emission sampling in a chimney, the traverse points for sampling are selected on the basis of:

(a) Equal gas temperature; (b) Equal emission strength; (c) Equal gas velocity; (d) Equal area; (e) Random sampling


Thank You


Air Pollution Meteorology

• Effect of solar radiation; heat balance of earth-atmosphere system

• Relationship of atmospheric pressure and wind: general circulation of the atmosphere; wind speed and direction; cyclones, anticylones, frontal systems, and air masses

• Vertical structure of the atmosphere

• Influence of topographic features on wind flow and dispersion

• Lapse rates (superadiabatic, adiabatic, subadiabatic), buoyancy of air parcels

• Plume rise, Effective plume height – factors affecting the plume rise

[Stack downwash/downdraught – Exit velocity < 1.5 x wind velocity]


Air Pollution Meteorology

• Atmospheric stability - importance of turbulence for dispersing air pollution

• Pasquill-Gifford stability class and associated weather condition

(e.g., sunny, calm wind)

• Temperature inversion - radiation, subsidence, frontal, advection

• Mixing depth/height

• Plume rise and plume behaviour under different stabilities –coning, looping, fanning, lofting, fumigation


Acid Rain

• Basics – acidity, pH (unpolluted air vs acid deposition), wet and dry deposition

• Causes, responsible air pollutants

(e.g., SO2 -> H2SO4/H2SO3), NO2 -> HNO3/HNO2)

• Effects

- Aquatic ecosystems

- Terrestrial ecosystems; soil and vegetation

- Human health

- Materials and visibility

• Responses and mitigation action


Photochemical oxidants

• Secondary pollutants produced by the action of sunlight on an atmosphere containing reactive hydrocarbons / volatile organic compounds (VOC) and oxides of nitrogen.

• Precursors and chemistry

• Meteorological conditions that favour photochemical oxidation

• Typical diurnal variation


Global Scale Air Pollution

• Global warming

• Causes; Greenhouse gases (E.g., CO2, CH4, halocarbons, N2O, O3, aerosols (sulphates, soots)); Global warming potentials; Radiative forcing of GHG ; Sources of GHG; Emission and GHG trends, IPCC’s scenarios, Possible adverse impacts

• Global responses - UNFCCC, Kyoto Protocol, Paris Agreement

• Stratospheric ozone depletion

• Good ozone - Ozone layer as a UV protective shield; Causes of ozone depletion; Ozone depleting substances (E.g., CFC, HCFCs, halons, methyl bromide, etc); Ozone depleting potentials; Sources of ODS; Catalytic destruction of stratospheric ozone, ozone hole; Impacts of increased UV exposure

• Global responses – Vienna Convention, Montreal Protocol

• Persistent organic pollutant (POP)

• Issues; Global responses – Stockholm Convention


Indoor Air Pollution• Major indoor air pollutants, sources and sinks

• Sick building symptoms, building related illnesses, Legionnaires’ diseases

• General understanding of the Hong Kong Indoor Air Quality Certification Scheme

12 parameters to be certified (CO2, CO, O3, NO2 , PM10, HCHO, TVOC, bacteria, radon , temp, RH, air movement); IAQ guidelines; how and who to certify.

• IAQ improvement: Ventilation (natural/mechanical; air changes, ventilation rates); Source control/removal, e.g., banning of cigarette smoking, high VOC paints and furnishings; Air cleaning/purification

• Simple Box Model for estimating IAQ, e.g.,

C(t) = Camb + (Cinit - Camb) exp(-Q t/V) + (G/Q)(1 - exp(-Q t/V)


Health Effects• Organs mostly affected by air pollution

• Eye, skin irritation – O3, NO2, PAN, HCHO, photochemical oxidants

• Cardiovascular system – CO, Pb, PM2.5/PM10

• Respiratory system – Bronchitis, Pulmonary emphysema, lung cancer, bronchial asthma, respiratory system infections – SO2, O3, NO2 , PM2.5/PM10

• Others – brain, nervous system,

reproductive system

• Vulnerable sub-population:

e.g., children, asthmatics, elderly

• Significance of particle sizes on health


Health Effects

• General awareness:

• Scientific studies of adverse health effects of air pollution –Epidemiological studies; Toxicological studies

• Excessive health risks: %ER = (eβC – 1) x 100%

• Life expectancy (L); Years of life loss (YLL; L x No. of deaths due to condition), Years lived with disability (YLD; No. of incidences in the population x disability weight x average duration of condition); Disability adjusted life year (DALY = YLL + YLD)

• Value of life: Willingness to Pay (WTP); Value of statistical life (VSL), Value of statistical life year (VSLY)

• Air pollutant with highest health risk (cancer risk, short-term, long-term health risks) in Hong Kong

• WHO’s estimated number of deaths globally attributable to

• Ambient air pollution: 3.7 M; Household air pollution: 4.3 M(http://www.who.int/phe/health_topics/outdoorair/databases/en/)


Air quality model

• Purposes: understand causes of pollution, estimate contributions of sources, air pollution forecasting/prediction, estimate pollutant changes/trends and impacts of different control scenarios in EIA, source reviews, air quality management plan, etc.

• Air Quality Modelling System:

• Types of models - Box, Gaussian, numerical, statistical, physical, receptor, etc. (E.g., Receptor Models - use observational data to estimate relative importance of different sources, rely on different chemical signatures for different sources types, assume little transformation of pollutants from source )

• Choice of model and factors affecting the suitability

Meteorological model (MM5/WRF)

Emission model (SMOKE)

Chemical transport model(CMAQ, CAMx)

Meteorological dataBoundary & initial conditionsEmission factors, activities, etc.


Emission Inventory

• 𝐸𝑖,𝑗,𝑡 = 𝑘 𝑙 𝑚𝐴𝑗,𝑘,𝑙,𝑚,𝑡 × 𝐸𝐹𝑖,𝑗,𝑘,𝑙,𝑡 ×𝑃𝑖,𝑗,𝑘,𝑙,𝑡 × 1 − η𝑖,𝑚,𝑡where: i,j,k,l,m and t stand for species, geographical area, sector, fuel type, emission control technology, time frame, respectively; A = activity level (e.g., energy consumption, industrial production, vehicle kilometer travelled); EF= unabated emission factor; P = penetration rate of the relevant emission control technology; η= removal efficiency of the control technology

• Choice of emission factors and

other parameters

• Uncertainty

• Hong Kong Emission Inventory


Gaussian Plume Model

• Ground level pollution concentration =

Q

2π𝜎𝑦𝜎𝑧u𝑒−12

𝑦𝜎𝑦

2

𝑒−12𝑧−𝐻𝜎𝑧

2

+ 𝑒−12𝑧+𝐻𝜎𝑧

2

• Gaussian dispersion coefficients – standard deviations of the horizontal and vertical Gaussian distribution

• Applications of Gaussian models

• Limitations: E.g., assume constant wind speed and direction; ignores obstacles, difficult terrains; not applicable for calm wind conditions; applicable within 50 km from the source


HKAQO, A Clean Air Plan

A Clean Air Plan issued in March 2013 by the ENB in collaboration with THB, FHB and DEVB• A comprehensive plan to improve air

quality and public health in Hong Kong


Air Quality Health Index (AQHI)

• 3-hour rolling average concentrations of NO2, O3, SO2 , and PM10

(or PM2.5 whichever the higher).

• Based on the sum of the additional short-term hospital admission risk (%AR) of respiratory and cardiovascular illnesses

Total %AR = %AR (NO2) + %AR (SO2) + %AR (O3) + %AR (PM)

• Threshold for issuing health advice set at the %AR at their

respective short-term WHO.

• On a scale of 1 to 10 and 10+, grouped into five AQHI health risk

categories, to enable the public make adjustments of their

physical activities according to their own health conditions.


Stationary emission source control

• Process changes, design/equipment modification, work practice changes

• Change to cleaner fuel / materials - e.g., low sulphur coal, coal to natural gas power generation, diesel to LPG taxis, low VOC paints

• Exhaust gas control - e.g., SO2: flue gas desulphurization/ scrubber; PM: EP, bag filter/baghouse, scrubber; NOx: low-NOx burner, SCR, SNCR

- Knowledge of the control equipment/ practices that are effective in controlling respective air pollutant emissions

- Working principles, operation and maintenance, limitations, significance of particle sizes

• Suitably designed stack/chimney, dispersion

- Knowledge on stack/chimney design


Mobile source emission and their control

• Spark ignition, compression ignition and their major emissions

• Air - fuel ratio

- stoichiometric A/F ratio for petrol (C8H18): 15 -- effects on emissions, power and fuel economy

• Emission control

• Evaporative loss, crankcase emissions

• Fuel change: e.g., diesel to LPG taxis, reformulated petrol,

ultra-low sulphur diesel, biodiesel

• Tail-pipe exhaust control: Petrol vehicles - three way catalyst; Diesel vehicles - exhaust gas recirculation, SCR

• Hybrid, LNG, electric, supercapacitor vehicles, etc.

• Inspection and maintenance and their significance


Mobile source emission and their control

• Regulatory control requirements, e.g., fuel efficiency, emission standards (e.g., USEPA, EURO), testing cycles

• Retrofitting programmes – e.g., diesel particulates control devices, SCR devices for NOx control

• Traffic management – e.g., low/zero emission zones, road pricing, pedestrainisation, cycling, mass transit, transport planning


Control equipment

• Cyclone - Centrifugal Separation, theoretical removal efficiency

η =𝜋 𝑁 𝑉𝑐 𝐷𝑝𝑎𝑟𝑡

2ρ𝑝𝑎𝑟𝑡9𝑊𝑖 𝜇

Limitation: low removal efficiency for small particles (< 5𝜇m)

• Fabric filters

- Types, efficiency of different fabrics; Cleaning methods –shaking, reverse air, pulse-jet; major variables affecting the performance - pressure , filter drag, air-to-cloth ratio / filtration velocity (cm/s/cm2); Typical air-to-cloth ratios (of different cleaning methods)


Control equipment

• Electrostatic Precipitators –

- charging the particles by ionization, transporting charged particles in the electric field to collecting surface, neutralizing charged particles precipitated on the collecting surface, transferring the collected particles to dust hopper

- Deutsch-Anderson equation

η = 1 − 𝑒 −𝐴×𝑣 / 𝑄

- Applicable to both large (e.g., power stations) and small (e.g., cooking fumes) operations


Control equipment

• Scrubber

- Spray tower, venturi scrubbers, packed tower (purposes of packing – provides larger gas-liquid contact surface, turbulent contact for better mixing, longer residence time and repetitive contact

- Factors affecting the performance - Liquid-to-gas ratio, gas velocity/residence time, gas distribution system, turndown ability, pressure drop, pH (for acid/alkaline gas)

- Applications - removal of particulates and/or gases from exhaust systems

- Flue gas desulfurization (FGD) – Type, working principles, waste disposal


Control equipment

• NOx Control

• NO formation – Thermal NOx, Fuel NOx,, Prompt NOx

• Temperature Effect N2 + O2 -> NO

• Control of NOx :

Fuel change; Combustion control (e.g., Flue gas recirculation, staged combustion, water/steam injection);

Conversion (e.g., Selective catalytic convertor (SCR), non-selective catalytic converter (NSCR))

• Genenal awareness of recent developments in controlling air pollution: e.g., photocatalysts, air cleaning towers, road barriers


Monitoring network design and operation

• Air monitoring objectives of monitoring network

• Air monitoring train design (SLAM, NAMS, PAMS, supersite, PSD, special purposes)

• Spatial scale of representativeness – micro (<0.1km), middle (0.1-0.5 km), neighbourhood (0.5-4km) , urban (4-50 km), regional, national, global

• Probe siting criteria - Horizontal and vertical probe placement, spacing from obstructions, spacing from roads, spacing from trees and other considerations

• Monitoring parameters

• Key meteorological variables (e.g., wind speed, wind direction, temperature, solar radiation, mixing heights)

• Gaseous and particulate pollutants

• Ozone precursors


Monitoring network design and operation

• Air monitoring methods / techniques

• Other relevant consideration

• Power, safety, security

• Probe materials: e.g., stainless steel 316, telfon, glass, brass

• Sample residence time, etc.

• QA /QC

• QC programme – e.g., Standard operation procedures (SOP), traceability, calibration (multi-point, zero/span check once every 24h) – zero/span drift, co-locating samplers, maintenance (preventive, repair), staff competence, documentation

• QA Programme – e.g., personnel responsibilities, data reporting procedures data validation procedures, audit procedures – data audit, equipment audit, system audit; internal audit, external audit


Ambient Sampling –Reference Methods

• Reference Methods

• E.g., SO2: paraosaniline method; NO2: Gas-phase Chemiluminescence with O3; PM: Gravimetric method; O3: Gas-phase Chemiluminescence with ethylene; CO: Nondispersive infrared absorption

• Equivalent methods

• E.g., SO2: UV Fluorescence; Particulates: Tapered element oscillating microbalance (TEOM), Partisol dichotomous air sampler, Beta ray attenuation; Class I, Class II, Class III equivalent methods; O3: Photometry

• Ambient Toxic Air Pollutant Measurements - E.g., Benzene, 1,3-Butadiene, etc (TO-14; canister); Benzo[a]pyrene (TO-13; polyurethane foam with XAD-2 resin); Dioxins (TO-9; polyurethane foam); HCHO (TO-11, DNPH)


Continuous monitoring systems

• Basic principles:

• Spectroscopic absorption methods, e.g., Nondispersive IR – CO, CO2

• Luminescence techniques, e.g., UV Fluorescence – SO2

• Chemiluminescence, e.g., NO, NO2, NH3

• Flame photometry, e.g., S containing gas

• Electroanalytical techniques, e.g., O2

• Paramagnetic techniques, e.g., O2

• Application, operation and maintenance


Source Monitoring

• Representative sampling location: e.g, 5D downstream, 2D upstream

• Particulate sampling

- Particle size issue

- Isokinetic sampling

• Standard/Reference condition:

- Dry, 0 degC, 101.325 kPa, 6% O2

- Why and how to correct to standard/reference condition

• Grab sampling vs Continuous sampling

Advantages/disadvantages (e.g., Limitation of grab sampling: less capable to capture worst cases )


Q&A

Hong Kong Institute of Qualified Environmental Professionals Limited …hkiqep.org/wp-content/uploads/2015/11/HKIQEP_Air_with... · 2016-07-14 · Title: Hong Kong Institute of Qualified

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