1. Griffin House
Market Street
Charlbury
Oxford OX7 3PJ
United Kingdom
Tel: (44) 1608 810110Dust and Air Quality Innovation and Expertise
Tel: +44 (0) 01608 810110 Web: www.dustscan.co.uk
What is in my dust?
Andrew Green
Senior Consultant โ Air Quality and Exposure
07 June 2018
2. About Me
โข Studied Environmental Science at University of
Portsmouth (2011-2014)
โข Graduated with BSc First Class
โข Joined DustScan later in 2014 as a Technical Assistant
โข DustScan specialise in air quality and dust consultancy as
well as providing bespoke dust monitoring equipment
โข Progressed over last 3.5 years to level of Senior
Consultant
โข Previously attended IAQM meet-ups and wanted to get
involved
3. My role and technical responsibilities
โข Air Quality Assessments for projects including industrial,
commercial and residential
โข Workplace Monitoring and Assessments for exposure to
substances, including dust
โข Project Proposals and Management
โข Supervising analytical work and reviewing reports
4. What is Dust?
โข It is widely accepted that dust is particles less than 75 ยตm
โข Naturally occurring, caused by a number of processes
including abrasion, erosion and combustion
โข Courser dust is responsible for loss of amenity
(Nuisance/disamenity)
โข Particulate matter regarded as fine particles, categorised
by size fraction.
โข PM10 - aerodynamic diameter less than 10 ยตm
โข PM2.5 - aerodynamic diameter less than 2.5 ยตm
5. Objectives and Standards
โข No Standards for nuisance dust but various guidance
(IAQM, EA) on recommended monitoring
โข There is a case for further investigation into dust nuisance
and loss of amenity
โข Environmental Standards included air quality objectives for
PM10 and target values for PM2.5
โข Target values for some metals, including Pb, Cu and Ni
โข Workplace (indoor) standards include all inhalable and all
respirable dust which are measured against workplace
exposure limits (WELs) set out by HSL in EH40/2005
โข Other standards and objectives in different countries
6. Investigating Dust Sources
โข Whatโs the reason for investigating? E.g. Occupational
concern, nuisance concern
โข Understand background sources, local geology and soils
โข Identify onsite activities that could produce dust
โข Who/what are the receptors? E.g. Workers, businesses,
general public
โข Consider control measures implemented and effectiveness
of mitigation
โข Assess suitable method for monitoring and investigation
7. Methods of Dust Analysis
โข Optical Light Microscopy: Visual interpretation using
different lighting conditions and high magnification
โข Scanning Electron Microscopy: Higher magnification,
some chemical data available when coupled with energy
dispersive spectrometry
โข X-Ray Diffraction: analysis on particle structure, used on
respirable samples for indentifying RCS
โข Inductively Coupled Plasma โ Mass Spectrometry:
Quantifies proportions of elemental composition
8. Case Study 1: Provenance of Warehouse
Dusts
โข Forklift truck tyres: rubber dust
โข Forklift truck brakes: metal
โข Concrete floor: mineral dust including calcite (CaCO3) and
possible quartz (SiO2)
โข Packaging, pallets and contents: cellulose fibres
โข Large doors: dust from yard and external sources
โข History of site: previous uses
โข Diesel forklift trucks or HGVs: Diesel Engine Exhaust
Emissions (DEEE)
9. Case Study 1: Microscopy
Figure 1: Example of warehouse dust under reflected
light
Rubber
(tyre)
crumb
Blue pallet
fibre
Cementitio
us material
Cellulose
fibre
Metal
fragment
10. Case Study 1: SEM-EDS
Figure 2: SEM high resolution
image of warehouse dust
Figure 3: False-colour element maps showing
carbon (C), iron and aluminium (Fe, Al),
calcium and oxygen (Ca, O) and silicon and
oxygen (Si, O)
11. Case Study 2: Source of metals in PM10
โข Previous study found elevated levels of certain elements
in PM10 samples, some metals above target values
โข Metal foundry identified as potential source
โข Installed directional and depositional dust monitors along
with gravimetric PM10 samplers
โข SEM-EDS and ICP-MS used to investigate elemental
concentrations in alloys
12. Case Study 2: SEM-EDS
Figure 4: SEM image of PM10 filter
13. Case Study 2: SEM-EDS
2 4 6 8 10 12 14
keV
0.0
0.2
0.4
0.6
0.8
1.0
cps/eV
C
O
Si K
K
Fe
Fe
Mg
Na
N
Cl
Cl
Ca
Ca
Al
S
S
Ti
Ti
Ni
Ni
Zn
Zn
Cr
Cr
Cu
Cu
Figure 5: Energy Dispersive Spectrograph of PM10 filter
14. So...Whatโs in my house dust?
โข Appling knowledge of dust sources, analysis through analytical
techniques including microscopy and SEM
โข Mostly dead human skin cells: organic material
โข Clothing fibres: fabric, cotton, wool
โข Carpet fibres, flakes of paint, plasterboard (gypsum)
โข Cellulose fibres from paper/cardboard/wood
โข Other organic material from food, plants, invertebrate
โข Material from outside: usually consists of minerals from local soils
and rocks
โข Urban areas: can contain tyre rubber, exhaust condensate and
other road dusts
โข Rural areas: can contain agricultural dust such as higher
proportions of organic fibres and pollen at certain times of the
year
โข Extreme events e.g. Sahara dust, volcanic dust
15. Thank you for listening
โข LinkedIn: www.linkedin.com/in/andrew-
green-1b422876/
โข Website: www.dustscan.co.uk
โข Email: andrewg@dustscan.co.uk