Environmental Dust Monitoring

Environmental Dust Monitoring – Local Air Quality: impact on our neighbours and the wider environment.

TSI – Nick Brown Regional Sales Manager UK & Ireland

6th July 2016

Agenda

+ Reasons why control is important.+ Methods of monitoring.+Air quality papers and research.+Guideline & regulation.+Summary.

05/01/23© TSI Incorporated 2

Agenda



Reasons why control is important


+ Scientifically-established harmful effects leading to research & regulations with the goal to protect

• Human health

• Environment

+ Nuisance effects

• Visibility

• “Dirty” environment

Reasons why control is important+ Health effects from particles and fibres from certain materials are

immediate while those from other types of materials may take many years to develop.

+ It is therefore essential that exposure to all forms and sizes of particle pollution is kept to a minimum, both for workers on site and for other people living and working outside the activity boundary.


Reasons why control is important+ Predicted daily incidence and prevalence of various health end

points in The Netherlands attributed to short-term exposure to indicated 24 h average PM-10 levels. Expressed as the number of persons affected each day in the Dutch population (15 million).


Health End Point 40 µg/m³ 140 µg/m³ 200 µg/m³

Early Mortality 13 50 73

Hospital Admissions 29 109 165

Asthma in Children (age 7-11) 600 2,700 4,400

Upper Airway Respir Symptoms 11,000 41,000 62,000

>10% Lung Function Decrements 0 230,000 150,000

5-10% Lung Function Decrements 390 460,000 240,000


+ Personal exposure and health research+ Compliance and regulatory pollution control strategies+ Evaluate effectiveness of remedial actions and assess exposure in

communities+ Timely public reporting, air quality index, and forecasting

-> Network of reference (equivalent) instruments- Expensive (purchase & cost of ownership)- Operator training, large footprint, power consumption



+ An environmentally friendly site is beneficial and the relevant legislation relating to the control of particles from construction, Industrial, demolition and related activity adhered to.

+ Construction site / industrial operators need to demonstrate that both nuisance dust and fine particle emissions from their sites are adequately controlled and are within acceptable limits.



+ Nuisance dust emissions from construction and other civil engineering activities are a common and well-recognised problem.

+ Under Part IV of the Environment Act, (1995) and the UK Air Quality Strategy, Local Authorities are required to work towards achieving national air quality objectives.

+ Dusts from various construction processes contain a wide range of particle sizes and material types (eg silica) and can cause both minor and serious health problems. They can also cause discomfort to the eyes, nose, mouth, respiratory tract and skin.



+The larger particles, usually termed dust, tend to settle out of the air quickly and are mostly a health hazard to the operators of plant and equipment and those in the immediate area. They enter the nose and mouth during breathing and settle in the upper airways.

+PM10 particles and smaller are usually invisible and may not seem to be an obvious hazard. However, they can be carried much further in the air and can cause health hazards both to workers on the site and to people living and working outside the site boundary in the local neighbourhood.


Reasons why control is important+ Potential effects of particles on people

+ Health effects from particles of dust can effect the skin, hair and lips and smaller particles getting into the deeper respiratory tract.

+ Air pollution can cause both short term and long term effects on health and many people are concerned about pollution in the air that they breathe.

+ People with heart or lung conditions, or other breathing problems health may be further affected by air pollution.



+ Potential effects of particles on People

+ Nuisance caused by surface soiling.

+ In the UK alone, it is estimated that the burden of long-term exposure to outdoor particulate air pollution in 2016 was an effect on mortality equivalent to nearly 40,000 deaths at typical ages and an associated loss of total population life of 468,965 life-years.*

+ This is thought to be higher if we consider indoor air pollution as well.

*Royal College of Physicians and the Royal College of Paediatrics and Child Health 2016


Reasons why control is important+ Potential effects of particles on the environment

+ Landscape & Loss of visual amenity through deposition.+ Nature conservation & Covering of the leaf surface, resulting in shading and

consequently reduction in net photosynthesis, altered pigment levels and/or reduced productivity.

+ Alteration of leaf surface chemistry that may affect disease resistance.+ Addition of nutrients from the dust that may lead to increased growth and/or deficiencies. + Cultural heritage


Reasons why control is important+ Potential effects of particles on the environment

+ Changes in soil pH levels over time if the dust has different pH conditions.+ Soil pollution via deposition from the air or water run-off.+ Creation of a surface film on still water bodies.+ Increase in suspended and dissolved material in water courses with knock-

on effects on aquatic ecology.+ Surface soiling and damage during cleaning.

Source: Adapted from Land Use Consultants, 1998



+ Benefit of an environmentally friendly site:+ An environmentally friendly site will help to establish good relationships

between the companies, contractors, regulators, local residents and others in the construction process, thereby helping projects to run smoothly.

+ Benefits will be felt at both corporate and project levels and include:

+ Lessening of the impact on local air quality

+ Reduction in the soiling of property, thereby reducing the costs of cleaning



+ Reduction in the level of complaint from local residents

+ Reduction in the number of environmental offences and hence prosecutions by Local Authorities

+ Less time and money wasted in defending prosecutions and repairing environmental damage

+ Reduction in the site engineer’s workload by avoiding conflicts



+ Historically, many of the materials produced during construction/operations have been subject to investigation and control, mainly with regard to occupational hygiene and the protection of the workforce.

+ More limited attention has been given to regulating the exposure of the general populace to these materials when they cross the site boundary.

+ There are some exceptions to this generalisation, asbestos for example is covered by specific regulations.



+ Producing acceptable workplace conditions does not necessarily create acceptable conditions for the

general populace beyond the site.

+ It is normal for much lower exposure levels to be required for the general populace, however the more vulnerable groups need to be protected:

Especially in buildings in proximity with inhabitants such as the very young & young , very old and infirm


Reasons why control is important+ Industrial Fence line / Industry (outdoor but also indoor)

• Real time monitoring allows immediate response• Demonstrate impact on local receptors / compliance• Corporate Social Responsibility

+ Air Quality Consultants / Engineering Offices• Tools for deployment on multiple client projects• Increased temporal and spatial analysis• Baseline Environmental Impact Assessment (EIA) studies

+ Municipal Networks• Supplement or extend the existing reference network• Mobile and hot spot monitoring• Special purpose / location monitoring

+ Universities and Research• Introduce practicalities of air quality cost effectively• Advance epidemiological research through higher temporal and spatial resolution


Reasons why control is important+ Environmental (non-regulatory) monitoring

• Fugitive emissions• Site perimeter• Fence line• Dust control operations• Hazardous waste sites• Remediation Sites• Forest Fires

+ Process monitoring• Mining industry• Paper mills• Grain mills• Foundry process monitoring


Agenda



Particulate Matter (PM) Is An Air Pollutant Based on Size+ Particles smaller than or equal to 10

microns (µm) diameter.+ How small is 10 µm?

Human Hair70 µm

Particles Come in Different Sizes

Source: Aerosol Measurement, Willeke and Baron, 1993, p.57

FINE PM COARSE PM

PM measurement

The true measurement of particulate matter (PM) mass concentration in ambient air is often difficult due to the physiochemical nature of the particles themselves and their interaction with the measurement methodologies employed.

Particle Matter Characteristics

+ Can exist in either solid or liquid form, or a mixture of both

+ Exist in equilibrium with their environment

PM

Nitrates

Salts(Na, Cl)

Aerosols

Soil

Organics(PAH’s)

Heavy Metals(Fe, Pb, Cd)

Dirt

Carbon (C)Dust

Soot

Smoke

Sulfates

Particle Morphology Particle Composition

• Generally NOT unit density spheres (often assumed for surrogate measurement methods)

• Can exist as crystals, aggregates, complex chains, rough surfaced spheres, hollow spheres

Water

Particulate Matter (PM)Mass Concentration

VMPM x

Where:

PM = Particulate Matter mass concentration [µg/m³] of particles less than x microns in diameter

M = Mass of sampled particles

V =Volume of air sampled

Collection

Sample Inlet

•No active conditioning – sampling at or near ambient conditions

•Sample filter is equilibrated to specified T, RH% (pre-sampling equilibration conditions)

•Sample filter is weighed

Reference PM Methods

USEPA and EuropeanFilter Conditioning Requirements

• USEPA PM-10Temperature range

15 to 30 deg CTemperature control

+/- 3 deg CHumidity range

20 to 45% RHHumidity control

+/- 5% RHConditioning period

At least 24 h

• USEPA PM-2.5Temperature range

20 to 23 deg CTemperature control


30 to 40% RHHumidity control


At least 24 h

Source: PM-2.5 Weigh Room Systems, USEPA; EN12341

• EN12341 PM-10Temperature range

20 deg CTemperature control


50% RHHumidity control


48 to 72 h

MCERTS


Reference & Equivalence - Definitions+ Reference is the defined sampling methodology used

to gather PM indicator data. It includes a combination of design and performance based criteria for both the sampler and subsequent laboratory treatment of the sample filter.

+ Equivalency is the comparison of a measurement method to a reference method (not a primary traceable standard).

Overview

+ Simple gravimetric air samplers developed over the past fifty years have gradually been augmented or replaced by continuous PM monitors to address the growing need for better time-resolved measure of particle-related air pollution.

+ Continuous monitor types for the measurement of particulate matter (PM) in ambient air include inertial microbalance, beta attenuation, and light scattering.

Direct (first principle) Methods+Gravimetric

• Manual, gravimetric determination of mass collected on a sample filter (e.g., laboratory balance)

+Inertial Microbalance• Automatic, inertial determination of mass collected on a

sample filter based upon first principle spring-mass law • (e.g., Tapered Element Oscillating

Microbalance, TEOM® monitor)

Inertial Microbalance+ Accuracy: ≤ ±0.75%+ Precision (1-hour): ±1.5 µg/m³+ Sources of potential uncertainty:

• Near real-time mass measurement may be affected by rapidly changing temperature or pressure conditions, leading to increased noise in the measurement.

• Requires stable temperature and flow regime.

Inertial Microbalance

• This inertial method provides an in situ, filter-based, direct mass measurement of PM present in ambient air by drawing a sample down a tube to a small exchangeable sample filter.

• The sample filter is attached to a hollow tapered tube that is maintained in a fixed amplitude oscillatory motion.

• As particles accumulate on this sample filter they are continuously weighed.

Indirect (surrogate) Methods

+ Beta Attenuation

+ Light Scattering photometer or OPC

Initial (factory) and onsite calibration is usually performed against a transfer standard or using assumed particle properties (which can change hourly, daily, seasonally).

Beta Attenuation• Provides a radiometric indication of the PM present in ambient air.

With this method, particle-laden air is directed toward a sample filter (either individual filter or filter tape) where the PM is collected.

•

• A mass determination is based upon the exponential attenuation in the number of beta particles passing through the filter media, collected PM and air gap between the emitter and detector. The emitter is a radioactive source commonly consisting of 14C, 85Kr, or 147Pm.

Beta Attenuation+ Mass Accuracy: unknown (mass transfer standard not

available)+ Precision (1-hour): typically ±10 to over ±20 µg/m³. + Sources of potential uncertainty:

• Beta attenuators are subject to error due to non-uniform filter media, non-uniform PM deposit, changes in air density, and PM deposit atomic number (especially presence of water vapor and lead).

• Initial (factory) calibration is often performed against a transfer standard beta monitor that has been calibrated for a known particle type (which can change hourly, daily, seasonally).

Light Scattering

• Provides a photometric indication of the PM present in ambient air.

• Two types of light scatter instruments exist for this purpose: single particle (optical particle counter) and group particle (photometer or nephelometer).

• Both utilize a light source, sensing volume, collimating or collecting optics, and a photomultiplier tube to sense the scattered light.

Light Scattering

• The single particle instrument counts and sizes particles one-by-one based upon the magnitude of the scattered light

signal as each particle passes between the light beam and detector.

• The group particle instrument determines the relative concentration of a population of particles in the sensing volume by measuring the integrated scattered light

(scattering coefficient) from the particles.

Light Scattering+ Mass Accuracy: unknown (mass transfer standard not

available)+ Precision (1-hour): N/A+ Sources of potential uncertainty:

• The mass concentration response of these methods is highly dependent upon the variation in the PM size distribution and chemical composition.

• In addition, single particle counter instruments have practical upper concentration limits due to particle coincidence (dead time) considerations.

Comparisons of methods+ Continuous PM measurement methods are often subject to

scrutiny in the following manner:

where: Cm is the PM mass concentration from a continuous methodCmref is the PM mass concentration from a gravimetric (reference) methodΨ is the relational factor between the two methods

+ In order to assure consistency and comparability of PM mass concentration measurements it is desirable for Ψ to be as close to unity as possible, provided that the measurements are made in thermodynamically equal environments.

mrefm CC

Comparison of methods.

+ Reference-equivalent or equivalent methods are defined through their comparability to a reference method.

+ Equivalency is the comparison of a measurement method to a reference method (not standard).

+ Accuracy is the comparison of a measurement method to a known standard.


+The approach used for equivalency comparison is as important as the definition itself. Most often, continuous (candidate) method Y is compared against gravimetric (reference) method X using a traditional linear regression treatment.

+The ratio of PM mass concentration (continuous to gravimetric method) versus the gravimetric method mass concentration can indicate issues related to the consistency of calibration.


Supplementing routine ambient air monitoring networks

• Better spatial coverage• Expanding conversations with communities• Enhancing source compliance monitoring• Monitoring personal exposures

The Changing Paradigm of Air Monitoring, Snyder et al, ES&T – October 2013


“Current sophisticated, expensive ambient air pollution monitoring technology is not economically sustainable as the sole approach and cannot keep up with current needs.”

Draft Roadmap for Next Generation Air Monitoring, US EPA – March 2013


Near-referenceSupplementary

StationsCost: €€€€

Data quality: A

Emerging Strategies

Existing

Strategy

IndicativemonitorsCost: €€

Data quality: B

Reference stations

Cost: €€€€€€€€Data quality: A+

Citizen scienceCost: €

Data quality: ?

Higher number of units

Lower price


The data from the EDT is of sufficient precision and quality to compliment existing air pollution monitors and networks

What are the Goals for PM Quantification?Continuous PM Monitoring in Air Quality Networks

+ Match the integrated reference (FRM) technique

+ Minimize cross-interference by humidity, thermodynamic conditions, gas composition

+ Use measurement methods that are NIST (primary standard) traceable

+ Provide representative short-term data for public reporting (air quality index, mapping, forecasting), health effects studies, and for control strategy development

Why are these goals difficult to achieve?+ PM is the only criteria air pollutant not defined by its molecular

composition

+ Particle-bound water can make up a large fraction of PM mass

+ Certain PM constituents can volatilize at ambient temperatures

+ The time-integrated “reference method” is not a scientific standard - only a method (indicator)

Agenda



Air quality papers and research.

+ Department of Environment, Food & Rural Affairs. (DEFRA)

+ The government strategy for improvements in air quality.

+ Available at:

+ https://www.gov.uk/government/publications/2010-to-2015-government-policy-environmental-quality/2010-to-2015-government-policy-environmental-quality


https://www.gov.uk/government/publications/2010-to-2015-government-policy-environmental-quality/2010-to-2015-government-policy-environmental-quality






+ Institute of Air Quality management.

+ The Institute of Air Quality Management (IAQM) is committed to enhancing the understanding and development of the science behind air quality by promoting knowledge and understanding of best working practices. Constructing buildings, roads and other infrastructure can have a substantial, temporary impact on local air quality. The most common impacts are increased particulate matter (PM) concentrations and dust soiling.



+ Greater London Authority –Control of dust and emissions updated in 2014

+ This best practice guidance forms part of the Government’s Air Quality Strategy with London local authorities having a responsibility to regularly to review and assess air quality and work towards achieving the air quality objectives set for various pollutants.


Agenda



Guideline & Regulation.

Source: EU Directive:2008/50/EC “Air Quality Directive”



+ Data quality objectives for ambient air quality assessment

Source: EU Directive:2008/50/EC “Air QualityDirective”





Criteria for number of monitoring stations:


+ Upper and lower assessment thresholds



Guideline & regulation.


Source: https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/182392/air-quality-legally-binding-objective.pdf

https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/1

Guideline and Regulation.

+ Greater London Authority –Control of dust and emissions updated in 2014

+ New London Mayor quoted:

“I have been elected with a clear mandate to clean up London’s air - our biggest environmental challenge,” Khan said at a school in east London.



+ Obligations of developer for Human and Ecological receptors:

+ 50m of boundary of site

+ 50m of route used by construction traffic up to 500m from site.



+ Increasing need for near reference real time monitoring.

+ Online - always accessible data

+ Alarm systems for pro-active actions.




Increasing public awareness of the issue via media exposure.

Increasing pressure from central government for enforcement by local authorities.

Vigilance of local Environmental Health Officers (EHO)

Increasing pressures for real time monitoring with alarms rather than just data logging.

Updated DEFRA guidelines published Sept 2015.

Agenda



Summary.


+ Many reasons for Environmental monitoring both for human and environment considerations.

+ Increasing focus from media, regulatory and legislative bodies.

+ Increasing need for combination of Reference and near reference, real time monitoring across multiple parameters.

Questions?