Category Archives: Dust Monitoring Equipment

Suspended Particulate Matter Definition – SPM and RSPM

There is much confusion about how to define PM10 particulate, but if articles indicate the definitions they used then the information can be compared with information from other studies. A concern is that the dust measurement equipment for PM10 particulate matter might not be designed to meet the same defined standard as used in the articles which could lead to some discrepancies.

Definitions of PM10 and respirable dust vary from

  • Particulate Matter with diameters less than 10 micron.  Not one particle collected may be above 10 micron, regardless of shape and density.
  • Particulate Matter with an aerodynamic diameter less than 10 micron.  This takes density and shape into account.
  • Particulate Matter with a d50 aerodynamic diameter of less than 10 micron.  This takes density, shape and statistical averaging into account.
  • Particulate Matter with a d50 aerodynamic diameter of less than 7 micron (Mining in South Africa).  This is just a lower cut off used in the South African Mining Sector of South Africa when determining respirable dust levels on workers working on the mines.

Similar confusion exists for the PM2.5 particulate definitions and the equipment used to determine these low particle sizes need to be well maintained and operated by experienced people to prevent contamination of the samples by particulate larger than the defined size.

The fact that respirable suspended particulate matter is more dangerous to health than larger particulate up to 100 micron is well established. It is important to remember though that the ratio of RSPM to SPM will be specific to an area and the measurement of the one should be able to infer the other if the ratio has been experimentally determined, (excluding air pollution modelling).

“RSPMs are more dangerous to health because they are much smaller than Suspended Particulate Matter (SPM), an umbrella term for all such substances with deleterious consequences, that are less than 100 micrometers in diameter.” See this link for the full article

At some stage the definition should be standardised so that apples can be compared to apples.

DustWatch particulate matter equipment measures SPM (suspended particulate matter), and is designed to have a cut-off at 100 micron, so that the maximum particle size collected is as close to 100 micron as possible.  The d50 of the samples is between 35 and 45 micron depending on the sampling location.  This is not an aerodynamic diameter as the size is determined using a Malvern particle size analysis.  So the d50 is the size of particle without taking density and shape into account.

Chris Loans

Dust Fall Manual and Procedures Updated

DustWatch Manual updated with Laboratory Equipment setup.  Dust Sampling Laboaratory Equipment.

Buchner Funnel Laboratory Setup and Procedures

Dust Monitoring Laboratory Equipment

Practical Fallout Dust Monitoring Training

Chris Loans – Training in Johannesburg for Fallout Dust Monitoring.

Practical training for two people was done in JHB by Chris Loans.

The training covered the following topics.

  • Preparation of Buckets.
  • Changing the Buckets in the units.
  • Filtering the samples
  • Postage back to the laboratory in Cape Town

The training was succesful and official documentation regarding the training was given to the two people being trained.

Please contact us for fallout dust monitoring equipment and training.  Courses run each month to suit the needs of those wanting the training.

Dust Monitoring Course – 11-13 July 2011

Fallout Dust Monitoring Course.  Theoretical and Practical Training.

The course will run on Monday, Tuesday, and Wednesday. 11 – 13 July 2011

The course has three main sections.

  1. Fallout dust monitoring theory
  2. Fallout dust monitoring practical
  3. Miscellaneous occupational hygiene topics.  Gravimetric sampling, isokinetic sampling, ventilation, noise, illumination, ergonomics, fire and safety, and others.

The fallout dust monitoring section of the course aims to train the trainees so that they are able to do the following.

  1. Understand what fallout dust monitoring achieves and what is collected.  This will include discussion around the legislative requirements and will also address the possible influences of dust sensitive areas like communities, hospitals, farms, and recreational areas.
  2. Prepare buckets, transport buckets and change buckets in the Fallout Dust Monitoring units.
  3. Filter the bucket contents using a filter bench and using the related equipment used in the filtering process.  This includes advice on how to minimise the filtering time and what can be done when samples are taking very long to filter.
  4. Understand how to calculate the fallout dust monitoring results in mg/m2/day and how to interpret these results.
  5. Report writing and presentation options for the results will also be discussed.
  6. Some computer training may also be included in the course if required.
  7. Access to our software for processing of the fallout dust data will also be included after the course.  This can be used to simplify the data collection and report writing and will also provide a database of the fallout dust levels over the years.


The course will be presented by Christopher Loans who is a Professional Chemical Engineer with a Masters in Occupational Hygiene focussed on the Mining Industry.

Yours faithfully

021 785 6999

082 875 0209


Day 1 and Day 2 proposed schedule.

Day 1

08:45        Registration
09:00        Welcome and Who is Who
09:15        Introduction to Environmental Monitoring – Fallout Dust
09:45        Discussion and Comments
10:00        What is precipitant Dust – Fallout Dust.
10:45        Discussion and Comments
11:00        Break
11:15        How to collect Fallout Dust
12:00        Discussion and comments
12:15        Particle Size and settling velocity.
13:00        Lunch
13:45        How to Calculate fallout dust results and Interpretation of the results.
14:30        Discussion and Comments
14:45        Trace Element Analysis and Fingerprinting
15:15        Break
15:30        Microscanning
16:00        General Discussion time and practical examples
17:00                End

Possible other topics for discussion:

·               PM 10 discussion
·               Relation of Fallout dust to PM10

Day 2

09:00        Welcome and Names
09:15        Practical training of bucket changes and filtering procedure.
11:00        Break
11:15        Report writing and presentation options for the results will also be discussed.
Computer training as required.  Any aspects of computer training can be discussed.  Computer
skills are important for performing tasks efficiently when using a computer.
13:00        Lunch
13:45        Access to our software for processing of the fallout dust data will also be included after the
course.  This can be used to simplify the data collection and report writing and will also provide a
database of the fallout dust levels over the years.
If time allows, other aspects can be discussed to suit the specific requirements of the people
being trained.
16:00        Discussion and Comments



Dust Monitoring Equipment in an Arctic Environment

We have not yet used our equipment in an Arctic environment but would look forward to using it in this environment. The coldest temperatures for units currently in use is about -3 DEG Celcius in Johannesburg, South Africa.

The four bucket equipment has one moving part that would need to move to enable the unit to work (The lid needs to rotate with the wind). The single bucket unit has no moving part used during the sampling period, but the unit can be lowered to change the bucket and we are not sure how very cold temperatures would affect that. The four bucket unit also has a lowering mechanism to allow for the buckets to be changed.

The buckets are normally changed monthly or two weekly to prevent the water in the buckets from evaporating, but in the Artic the water is unlikely to evaporate as quickly and this could affect how the sampling programme is designed. Provisionally, our recommendation would be to change the samples monthly or quarterly.

The DustWatch unit is designed to only collect particles when the wind speed is below 3m/s and predomainaly collects dust when there is little to no wind. The particle sizes collected range from 0 to 100 micron.

The buckets contain water to capture the dust when it is in the buckets. Some anti-freeze would be required to prevent the water from freezing in the buckets. The buckets used are made of Plastic and we are not sure how this will cope under very cold conditions.

We supply robust Buchner funnel laboratory equipment for use with the sampling programme. Samples make up a small package and can then be sent for weighing to any laboratory or to us in Cape Town. We will also be able to generate the regular reports if required.

The main products we supply are shown here.

Transportation costs would be worked out on the dimentions and weight of the package and we normally let the client arrange the transportation independantly from Cape Town South Africa.

New mining equipment to boost fight against silicosis

‘XRD’ is the new buzz word in the CSIR mining research group’s corridors.

This new piece of equipment, also known as theBruker D8 Advance, is an advanced X-ray diffractometer that promises to speed up and improve the quality of the CSIR’s laboratory analysis of silica dust.

“Respirable silica is a serious health concern in the gold mining industry,” says researcher Cecilia Pretorius. “Exposure to silica dust causes silicosis, a deadly lung disease, which is a major concern for the South African mining industry.” The XRD can analyse the phases or crystal forms of a material to determine the substances that are present in a specific sample. In mining it is used to determine what proportion of a dust sample consists of quartz. “It is the quartz component of the silica dust that is the culprit,” says Pretorius. Read more »

Dust Is Not Dust. Or Is It?

The information here on dust covers basic information and knowledge that all Environmental Practitioners, Occupational Hygienists, Ventilation Engineers and health professionals, as well as health safety professionals should not only have a working knowledge of, but should be able to apply.  While omitted from the above list, the Architect or Architectural Technologist should equally be aware of and apply the above principles, as the confining of an atmosphere containing dusts will increase the health risk associated with persons moving, living or working in the area or “space” – residential, office or hospital.

Dust by definition can constitute any particulate or matter fine enough to become airborne and will include rock, solid materials, organic substances, vapours, fumes, mists, fogs, smokes and under the correct conditions, fine gravels, flaky material, fibres, moulds, bacteria, microbes or small and sub-micronic insects.

Full Article Here