Monthly Archives: December 2021

Mining Related Deaths

This is always an issue that we want to see improved.  The work environment should be kept as safe as possible!
Mining Related Deaths
Source –
“SA was aiming to end mine fatalities – instead, more miners are dying accreditation
Sibongile Khumalo
SA’s mining industry and unions are concerned about an increase in mining-related deaths.
The year 2019 was the safest year on record with 51 deaths.
SA’s deep gold mines, followed by platinum, lead the sector in terms of high fatalities.
Although South Africa’s mining industry has been aiming to reduce mine fatalities to zero, the latest figures instead show an increase.
On Thursday, the Minerals Council of South Africa (MCSA) said a total of 32 mineworkers had died to date this year in the country’s mines – an increase from the rate seen a year ago.
In 2020, as the industry navigated the emergence of the Covid-19 pandemic – which hobbled full capacity operations in the initial months of the hard lockdown – some 24 mineworkers were killed in accidents.
While this was progress for South Africa, the International Council on Mining and Metals found, in its 2020 report, that SA had accounted for half its members’ fatalities.
The number of SA mining fatalities in 2018 had stood at 81.
South Africa, which has some of the world’s deepest mines, once had the worst health and safety record in the world. But since 1993, it has gradually been working to turn this around. The year 2019 as the safest on record with 51 deaths.
The country’s deep gold mines account for this year’s highest number of deaths in the period to 5 July, followed by platinum operations.
The MCSA, as well as other stakeholders such as labour unions and the Department of Mineral Resources and Energy, on Thursday expressed concern at the rise in mine fatalities at a time when the industry was also dealing with a pandemic that had so far killed 480 mineworkers.
What’s causing the deaths?
This year, there has been an increase in “fall of ground” accidents, particularly in the gold sector, with general accidents in mines also being on the upward trend.
The president of the MCSA, Nolitha Fakude, said while Covid-19 – which has devastated the industry for nearly 18 months – was still a challenge, it was crucial not to overlook a deterioration in mining’s safety performance.
“Worse still, thus far in 2021, we are seeing a further deterioration in the fatality trend,” said Fakude, as the council launched the National Day of Health and Safety in Mining.
Themba Mkhwanazi, who is the chairperson the Minerals Council’s Zero Harm Forum, said the situation called for collaborative efforts by the industry in order to arrest the trend.
“The CEOs must drive health and safety improvements from the top by sharing successes and challenges in dealing with occupational incidents,” said Mkhwanazi, who is also the chief executive of Kumba Iron Ore.
In addition to their depth, South Africa also has some of the oldest mines in the world. The sector has over the past year seen a mixed bag of reports in terms of mine-related deaths – as well as other health concerns.
The Chief Inspector of Mines, David Msiza, said while there had been a reduction in occupational diseases, the incidence of noise-induced hearing loss and occupational lung disease was still a concern.
Illegal miners’ battle to survive
While the industry is grappling with safety incidents in regular mining activities, government is also facing the scourge of illegal mining, which often results in deaths, as groups known as “zama-zamas” battle for territory or die in disused shafts.
In June, 20 bodies of people believed to be illegal miners surfaced on a site of a disused mine on Orkney, in the Free State.
Illegal mining deaths are not accounted for in the official incidents.
In addition to safety concerns over unregulated mining activities, Msiza said some illegal gangs were becoming violent.
He said illegal miners who were initially concentrated in the Free State were increasingly becoming active in Mpumalanga and the East Rand.
The Department of Mineral Resources and Energy has been driving the sealing of disused shafts in various parts of the country, but the reopening of holes by syndicates has seen officials playing cat and mouse with zama-zamas.
“If we don’t deal with the market, then we will struggle. Our other approach is to promote illegal mining through the issuing of licences to groups that want to operate with the legitimate legal framework, ” he said.
This article has been updated to reflect that the ICMM said 50% of fatalities were among its members. It does not include non-members in its analysis.”
Dust Monitoring Equipment – providing equipment, services and training in dust fallout management to the mining industry.

Merry Christmas 2021

We wish all our customers and clients a blessed Christmas season for 2021.

Microscan Assessments of Find Particulate Matter Samples



Microscan Assessments of Find Particulate Matter Samples

Image 1: The microscope currently being used.  UB100i Biological Binocular – 4 eye magnifications. UOP. SKU: SW-70051-BS-UB100i.  See specifications in Appendix A.

  • Introduction
    MicroScans are merely a description of accepted geological and other procedures for the recognition of rock fine material and other airborne material, distributed through-out a captured sample.
    While there are many more accurate quantitative analytical procedures, almost all are extremely expensive and all have limitations as they are designed for one purpose without considering other tests that may need to be done on the sample.
    It is important to interpret the results from such quantitative tests with the assistance of the background knowledge of how the sample was taken and site specific information.
    Often laboratory reports are only of academic value and do not bring new information to the table to assist in interpreting the results. The basics of any analysis is that it must provide additional information that is useful for the interpretation of the data being discussed.
    Spectrographic analysis is fine for the various mineral elements or individually for various compounds and element combinations, but all of the organic matter has to be either ashed or acid digested, and thus unless you have done a huge bulk sample capture, you will use up all of the sample to arrive at the elemental content.
    You will then need more material to be able to look at the organic chemistry type contents and yet a third sample to be able to look at the biological content and so on.
    Again, while not the perfect solution, the MicroScan is an intelligent scrutiny of samples that does not destroy or contaminate the sample.
  • Accuracy and Application

Things of concern in establishing the accuracy of any analytical method, as with field and laboratory geology, the initial recognition of a sample will rely on the colour of the sample, the hardness, form of the material in its normal state, and its propensity to break along fracture planes.  The fact that there is a list of geological materials falling into various hardness categories, which are used to establish how hard the material is, with harder material always damaging material of a softer hardness.
Other features of geology of use are the lustre presented on broken surfaces, and the crystalline structure of most minerals.
No matter how small the particulate may be, this will, in most cases, still display its crystalline form.  The hardness of each will then predict how fine dust material will wear, especially when driven over on roadways, quarries, and on dumps.  As dirt can be exceedingly small, this is the scale we need to work at and thus it is imperative that samples can be viewed at anything from scores, hundreds or even thousands of magnifications.  The advent of the digital imaging and various light sources, permits us not only to make observations but to photograph the noted features and specimens present.
The existence of a microscopic world out there also offers an opportunity to find microscopic life forms, or sub-micronic material and the larger more common pollen spores, algae, bacteria, and moulds which can influence health.  These potential health impacts are a concern and do impact on the health of people exposed to them.
Silicosis is caused by fine silica dust, and anthracosis is caused by fine coal dust.  Other forms of respirable disease are caused by other fine dusts, and the MicroScans enable the identification of fibres as well as fine organic material that can have a health impact.
It is a great big “tiny world” out there and there is no reason to only consider the mass of fine particulate matter, PM2.5 or PM10 or even PM30, but why not look for fibres which are present in airborne dusts, spores, moulds and other material which all have largely been ignored with regarding to their impacts on health.
The fact that collection methods only consider a material that remains after ashing or digestion also misses the golden opportunity of seeing what inaccuracies occur in many of the well-established and accepted methodologies.
The MicroScan technician in this case has to have a skill set and the skill base we work from is the knowledge of geology, occupational hygiene, organic chemistry and finally biology.  There are also some elements of forensics.

  • Sample Preparation

Ideally samples should be in a standard, 47mm petri slides with a tight fitted lid.  This allows the sample to be easily sealed when not being MicroScanned.
FFP1 or FFP2 respirators can be used to prevent the inhalation of fine respirable particulates.
Gloves should not be worn, as the combination of fabrics could cause static and the possible loss of fine material.
Forceps must be used to handle any samples.

  • Observations, Digitised Images and Preparation of Report photographs

The samples are scanned, and a representative image selected.  All size fractions are determined using a graticule.  The graticule size starts at 10 Micron and allows for the d50 diameter of a samples to be estimated.
The image is selected for photography if required.  Should there be any features or unusual material in the sample or a biological specimen, then this can be photographed, either in addition to or instead of the predominant particulate on the filter paper.
The photograph can be taken at four magnifications depending on the requirements.


The Microscope has four magnification (mag) settings, 4x, 10x, 40x, and 100x as a field lens.  The eye piece increases the magnification by 10x, and the camera increases it by 100 times.  The camera is fitted to the top of the microscope and the eye piece magnification is not included.

The total length of the gratical in the image below is 1mm from end to end.  Each small line indicates a gap of 10 micron, each medium line is a gap of 50 micron and each long line is a gap of 100 micron.

Image 2:  The above image photographed at a magnification of 4x field lens and 100x optical camera image, totalling 400 magnifications.

Image 3  The above image photographed at a magnification of 10x field lens and 100x optical camera image, totalling 1000 magnifications.

Image 4:  The above image photographed at a mag of 40x field lens and 100x optical camera image, totalling 4000 magnifications.

Image 5:  The above image photographed at a mag of 100x field lens and 100x optical camera image, totalling 10000 mags.
In practise this magnification cannot be achieved as the LED light source is not good enough to illuminate through the clear glass graticule, as can be noted by the image.

Note that the scaling is only applicable if the original image from the microscope is viewed at 100% size, and if the image has not been digitally resized.  The images above have been digitally resized.

There are some unknowns when doing MicroScans as described above and this should be considered when interpreting the results.

MicroScan assessments are a collection of recognised Geological and structural techniques utilised at microscopic level to determine the gross contents and salient features of any sample.  Crystallography also plays a significant part in the structural determination of materials making up the various constituents of the sample.

As the digitised images will also play a part in the recognition of certain constituents these can be further manipulated permitting viewing using polarised light and other means of illumination.

Our initial problem with some samples (unless taken by DustWatch in the field) is a common one shared by most laboratories running any form of assessment or analysis and that is that samples are supplied “blind” without any background information.  This means that we need to start making assumptions about unknown sampling procedures, exposure or capture times, methods or even any unusual circumstances surrounding the sampling conditions.

It is important to not put two samples together in one container as there will be cross contamination during transport and handling.


Gerry F. Kuhn (FMVS, MSAIOH, Grad SE) Chris Loans

(BSc Chemical Engineer, Pr Eng, MSc Public Health)

Doc Number:  0421291124  Date:  29-Apr-21

Appendix A:

___________________Extract from
(Accessed August 2018)_____

Binocular Microscopes > UB-100i

UB-100i Advanced Binocular Laboratory Microscope 
Full sized laboratory standard instrument of modern ergonomic design, robust reliable construction and excellent optical performance.
Equipped with infinity-corrected achromatic optical system. Chromatic aberrations and field curvature of field are both ideally corrected over the field of view. Infinity objectives, with higher numerical apertures, produce crisp and clear images..
Ideal for use in colleges, universities and professional laboratories over a wide range of biological, medical, veterinary, bacteriological and agricultural applications. Highly recommended.

Technical Specification: 
* Magnification range x40, x100, x400 & x1000
* Paired x10 DIN standard high eyepoint, widefield Plan eyepieces. Field 18mm, eyepoint 21mm
* Infinity achromatic objectives DIN standard Parfocal, parcentred x4(0.13),x10(0.30),40R(0.70),x100R(1.25) oil immersion (R=retractable)
* Bright field ABBE condenser (N.A. 1.25) with colour-coded iris diaphragm scale and filter carrier on fully focusing Substage
* Build in 230v, 6v 20w halogen illumination with continuously variable rotary brightness control
* Co-axial coarse and fine focusing with indexed scale and adjustable focus tension
* Smooth action x-y mechanical stage 142x135mm with co-axial drop controls and an adjustable spring arm to accommodate slides of different sizes
* Smooth action x-y mechanical stage 142x135mm with co-axial drop controls and an adjustable spring arm to accommodate slides of different sizes
* Seidentopf binocular head, inclined 30 degrees Rotatable 360 degrees with full inter-pupillary adjustment (52-75mm). Magnification factor x1
* Reversed position quadruple objective turret on sealed ball bearing race
* Complete with dust cover
* Supplied in polystyrene pack
* Dimensions 270x190x340mm
* Weight 6.5kg


______End of Extract from (Accessed August 2018) _

Appendix B

Additional reading material (Links accessible in August 2018 but may have changed since then)

Appendix C

Particle Size Theory

The South African national definition of PM10 particulate size is given as particulate matter of a size less than 10 micron.

The definition of any particle size has to include the density and the shape of the particle.  To understand PM10 particulate (or any particle size definition) additional definitions need to be understood and taken into account.

  1. PM10 – Sampling of atmospheric dust where the aerodynamic d50 diameter is 10μm.
  2. Aerodynamic diameter is the diameter of a spherical particle that has a density of 1g/cm3 and which has the same terminal settling velocity as the particle of interest.
  3. d50 – In a sample of dust the d50 diameter is the diameter above which fifty percent of the particles are larger, and below which fifty percent of the particles are smaller.
  4. d90 – In a sample of dust the d90 diameter is the diameter below which 90% of the particles are smaller.
  5. Terminal settling velocity is the fastest velocity that a particle can fall by gravity taking into account the shape and drag of the particle.

WRAC – Wide Range Aerosol Classification

TSP – Total Suspended Particulate

“The percentage of total aerosol mass less than 10 micron varied from about 50 to 90%, depending on the sampling location and sampling conditions.”  (R. M. Burton & Dale A. Lundgren (1987) Wide Range Aerosol Classifier: A Size Selective Sampler for Large

Particles, Aerosol Science and Technology, 6:3, 289-301, DOI: 10.1080/02786828708959140

To link to this article:

“PM10: The mass concentration of particles smaller than 10 μm. In practice, PM10 samplers do not provide perfectly sharp cuts at 10 μm. Instead, size-dependent collection efficiencies typically decrease from 100 percent at ~ 1.5 μm to 0 percent at ~15 μm, and are equal to 50 percent at 10 μm.” Referenced from

From the above it is important to note that larger particles can be collected if they have a low density as is the case with organics.

Gold Bearing Areas

Let’s learn about how do identify gold bearing areas from ( )

Gold Bearing Areas

“How to Identify a Gold Bearing Area

Updated April 25, 2017
By Chiara Sakuwa

Gold prospecting and identifying gold-bearing areas have become increasingly more feasible, due to research developments on the geological process of gold formation. (See References 1.) Gold bearing areas, mostly throughout the western United States, have drawn and sprouted entire communities based on prospecting. (See Reference 1.) Various hypotheses exist on how gold is formed as it surfaces in numerous types of volcanic and sedimentary rocks. Gold is mainly found in two types of deposits: lode (hard rock veins) and placer (surface). Locating the richest gold bearing areas primarily involves research, planning, dedication and funds. In other words, those who study geological surveys, land formations, rock structures and gold prospecting history prior to prospecting may have a better chance of finding desired amounts of gold. (See References 1 and 3.)

Research the geological properties of a particular gold-bearing area of interest. These properties include the rock formations, structure, fault lines and the primary mineral content of the area. Also, study the mineralization process of gold in general to determine which segment of a particular area may yield gold. (See Reference 1.)

Assess whether the area of interest is a lode deposit or placer deposit to determine proper equipment and prospecting methods. A lode deposit, consisting of hard rock usually found in a mine, mine dump or quartz vein will require a pick axe, hammer and chisel. Prospecting in a placer deposit, usually a stream, gravel lot or beach, requires a pan or dredging equipment. (See Reference 3.)

Plan your prospecting excursion according to your research. Gather the appropriate equipment. Map out the area and pinpoint the exact location you plan on prospecting for gold. Also, check state and local government regulations on gold prospecting respective to that particular region. (See Reference 2.)

Things You’ll Need
Dredging equipment
Geological survey map
Gold pan
Pick axe
Rock hammer

Due to the fact that gold is more weather-resistant than the rocks containing it, gold nuggets and fine particles can be washed down to concentrated placer deposits, or “pay streaks” by gradual erosion. (See Reference 1.)

Prospecting for gold often requires a large amount of funds for travel, accommodations and off-roading vehicles, without real promise of a good find, in most cases. In other words, a prospector must hope for the best, but be financially and psychologically prepared for the worst. (See Reference 2.)

Some gold-bearing areas, including national parks, are closed to prospecting. Violations may accrue major fines and in more serious cases, possible jail time. (See Reference 2.)

If a gold-bearing area is on privately-owned land, be sure to obtain permission from the owner in writing prior to prospecting. (See Reference 2.)”


Dust Monitoring Equipment – providing equipment, services and training in dust fallout management to the mining industry.

Generic Report

Below is an example of a generic report that DustWatch produces for it’s clients.





1 JUNE TO 28 JULY 2018


1     Introduction

This report covers a 57-day period.

The unit design and methodology are based on the ASTM D1739 standard.

Additional information is available in the DustWatch manual.  Please contact us to enquire about the latest version of the manual;

The area of the bucket used in the calculations is 0.022966m2.

There are three units installed and operating on site.  (GPS positions and a map will be added when they are available)

  • Unit 2 – Evac –
    Unit 3 – Carport –
  • Unit 4 – Francis –


Generic report - DustWatch cc

Figure 1:  Location of the units.

2      Comments on the result

There are three single bucket units installed and operational at the site, namely the:

  1. Unit No. 2 – Evac (SB2)
  2. Unit No. 3 – Carport (SB3)
  3. Unit No. 4 – Francis (SB4)

The fall-out dust standards from National Dust Control Regulations, 2013.

Restriction Areas Dustfall rate (D) (mg/m2/day) – averaged over 30 days. Permitted frequency of exceeding dust fall rate
Residential area D < 600 Two within a year, not sequential months.
Non-residential area D < 1200 Two within a year, not sequential months.

Table 1:  Acceptable Dust Fall Rates – National Dust Control Regulations, 2013.

  • The Evac unit yielded 299 mg/m2/day in this period. The result decreased and is compliant in this period.
  • The Carport unit yielded 290 mg/m2/day in this period. The result is not a concern.
  • The Francis unit yielded 290mg/m2/day in this period.

The results are below 1200_mg/m2/day and are not a concern.

Unit name Residential or Non-residential Area Applicable Compliance – Dustfall rate (D) (mg/m2/day) – averaged over 30 days. Non-compliant or compliant.  Two within a year, not sequential months.
Unit No. 2 (SB2)
(Non-residential) D < 1200 Compliant in this period.  Compliant for the year.  Exceedance in January.
Unit No. 3 (SB3)
(Non-residential) D < 1200 Compliant in this period.  Compliant for the year so far.
Unit No. 4 (SB4)
(Non-residential) D < 1200 Compliant in this period.  Compliant for the year so far.

Table 2:  Compliance Table 2018

Chris Loans

(BSc Chemical Engineer, pr eng)

Cape Town, Doc Number:  0718191208: Date:  19-Jul-18


Weather Information – Weather


2018 Temp. (°C) Dew Point (°C) Humidity (%) Visibility (km) Wind (km/h) Precip. (mm) Events
May high avg low high avg low high avg low high avg low high avg high sum
2 18 14 11 15 13 11 100 88 71 19 10 0 32 13 39 2.03 Fog , Rain
3 23 18 12 14 11 10 94 67 39 31 19 10 27 16 0.00
4 29 18 8 11 8 6 93 58 15 19 17 10 14 6 0.00
5 21 16 11 14 9 4 88 61 30 31 24 19 35 14 0.00
6 23 17 10 14 12 9 100 79 40 31 20 7 21 6 0.00
7 23 18 13 15 12 5 94 63 26 19 13 10 48 16 1.02 Rain
8 17 15 13 13 12 9 94 80 62 31 11 4 52 32 63 2.03 Rain
9 19 14 10 11 9 7 88 69 39 31 14 8 23 14 0.00
10 20 14 8 11 9 6 94 77 31 31 21 19 16 6 0.00
11 19 14 9 12 10 7 100 81 41 19 12 6 27 11 0.25 Rain
12 20 17 13 14 12 11 100 81 52 31 13 10 23 14 0.51 Rain
13 19 13 8 13 12 9 100 81 58 31 13 2 27 13 40 0.00 Fog
14 21 17 13 14 12 11 94 76 48 31 23 10 29 16 0.00
15 23 16 8 14 11 6 100 85 40 19 6 0 13 6 0.00 Fog
16 29 19 9 13 9 6 94 62 16 31 25 19 16 8 0.00
17 23 19 16 15 14 11 94 73 47 31 23 10 21 16 0.00
18 29 20 12 15 12 9 94 67 23 31 21 19 16 8 0.00
19 24 19 13 13 12 9 88 68 35 31 26 19 23 8 0.00
20 21 18 15 15 14 11 94 80 64 26 13 7 34 18 0.51 Rain
21 18 17 15 15 14 13 94 87 75 19 9 2 40 31 9.91 Rain
22 19 17 13 14 12 11 94 76 50 26 12 4 39 26 0.00 Rain
23 19 17 14 15 14 13 88 79 62 31 12 6 50 29 0.00 Rain
24 17 16 14 16 14 10 100 87 68 19 9 3 39 24 5.08 Rain
25 19 13 8 12 11 7 94 78 48 31 15 10 19 10 0.00
26 21 13 6 13 9 6 100 82 40 31 13 1 14 5 0.00 Fog
27 22 14 7 13 9 6 100 79 32 31 19 0 10 5 0.00 Fog
28 18 14 12 14 13 12 94 86 74 19 10 3 47 23 58 5.08 Rain
29 17 13 9 12 10 7 94 79 49 31 13 6 19 10 0.00 Rain
30 17 12 8 12 9 8 94 80 58 19 12 10 27 13 0.76
31 17 14 13 13 12 11 94 83 68 26 10 2 61 32 72 23.11 Rain
2018 Temp. (°C) Dew Point (°C) Humidity (%) Visibility (km) Wind (km/h) Precip. (mm) Events
Jun high avg low high avg low high avg low high avg low high avg high sum
1 17 13 10 13 9 6 94 69 39 31 11 3 60 34 80 0.00 Rain



CLIENT: gaositoe mmoledi Period Exceeds 40 Days SAMPLING PERIOD    –  1-Jun-2018 28-Jul-2018
SB2 Evac 1-Jun-2018 28-Jul-2018 206 X501 299

Table 3: Fallout Dust Results

CLIENT: gaositoe mmoledi   SAMPLING PERIOD    –  28-Jun-2018 28-Jul-2018
SB3 Carport 28-Jun-2018 28-Jul-2018 200 X502 290

Table 4: Fallout Dust Results

CLIENT: gaositoe mmoledi   SAMPLING PERIOD    –  28-Jun-2018 28-Jul-2018
SB4 Francis 28-Jun-2018 28-Jul-2018 200 X500 290


Table 5: Fallout Dust Results

Calibration and SANAS Information

The calibration is shown to four decimal places of a gram and is accurate to 0.1 mg.



 Appendix – Ligno Sulphate Information – Chryso Eco Dust 200D

DustWatch can provide quotations for this product if required and also provide advice on optimized application for different area requirements.  Gravel Roads, Haul Roads, Unpaved open areas, Stockpiles and Berms.  On site advice is available for site specific requirements and optimization.

The application spreadsheet is available here if required.


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