Category Archives: Dust & Environmental Hygiene Info

Fog Dust Suppression


Fog Dust Suppression

Vehicle Exhaust Emission Control for Gas and PM10 Particles

 Vehicle Exhaust Emission Control for Gas and PM10 Particles

PM10 and PM2.5 definition

PM10 and PM2.5 Definition

The subset point is worth remembering.  The simplistic definition is probably a good idea for public forums but this could lead to problems if things get a bit technical.  D50 and aerodynamic diameter need to be considered when getting technical about PM2.5 and PM10 particulate, not to mention the density of the particles being considered.


Overburden Blast – Blasting During Low Wind Conditions

Overburden Blast – Blasting During Low Wind Conditions

Wind Speed during a blast will significantly increase the movement of the the dust particles below a D50 of 30 Micron. Other factors will be the temperature and the humidity during the blast so time of day for the blasting is also an important variable to consider.

Mine Blast 60m From Digger – Dust Movement during a blast

Mine Blast 60m From Digger – Dust Movement during a blast

The Use of Noise Dosimeters in the Workplace

The Use of Noise Dosimeters in the Workplace

Some more information about noise dosimetry.

Sound level meter – Wiki Information

Sound level meter

This site has lots of great information on noise

Noise Monitoring and Respirable Dust Training

DustWatch cc will be doing Training in Somerset West on the 14th of August for Occupational Noise monitoring and Environmental noise monitoring.

Respirable Dust Monitoring and other occupational hygiene topics will be discussed.

______________________ Extract of Material_____

5.1 82 OR 85_dBA
As mentioned above it is easy enough to decide on a value and then call it something, but as soon as the term ‘significant risk’ is attached then there is an onus to prove the significance of the risk that as far as we are aware cannot be done. The value up to which there is no significant incidence of noise induced hearing loss in a worker spending a working period of 30 years in a fixed set of circumstances has been established world wide and accepted as 85 dBA. With this having been established there is little moral justification for considering a value lower than 85 dBA unless this is called something else.
The oft-quoted argument that noise induced hearing loss is on the increase in South Africa and this justifies a lowering of the value also has little substance, as this is not happening elsewhere and thus we must conclude that the South African fault must surely lie not in the working conditions but rather the extramural activities. If this is a generalised case then dropping the work related exposure rating from 85 dBA to 82 dBA will not compensate one iota and in fact now starts to infringe on the rights of the employer who should not have to drop his noise levels in order to dilute the levels being experienced at home or on the worker’s way to and from home and work. Noting 82 dBA as an action level is a good idea and one that all authorities can support.
The DME and DOL are also suggesting that noise areas should show continuous improvement from year to year. This is really a good idea and annual determinations will indicate any improvement or deterioration. The department of Labour argument that this should be considered only every second year extends the areas of risk to an unacceptable extent and it can be pointed out that an exposure of only 86 dBA on a continuous basis will almost guarantee an indication of hearing loss of a permanent nature in about a year.

5.5 Environmental Noise Report
With the enactment of the National Environmental Management: Air quality act the clamp down on Environmental Pollution is likely to precipitate a move towards application of the noise regulations with regard to affected communities.
Application of the new SANS 10103 – 2004 is to be welcomed in part as the limits make sense and are more achievable. The present Provincial Legislation is to be brought in line with the National NEMAQA– 2004 which brings SANS 10103 into contention.

5.5.1 New Legislation Principles
The NEPA Section 31 (1) stipulates that national standards can be prescribed

(a) “For the control of noise, either in general or by specific machinery or activities or in places or areas; or

(b) For determining –
(i) A definition of noise, and
(ii) The maximum levels of noise.”

Section 31 (2)

“When controlling noise the provincial and local spheres of government are bound by any prescribed national standards”
This contrasts to Air Pollution where the National, Provincial and Local governments can set standards providing that those set by the Province and Local authorities need to be more stringent or at least the same as National Standards.
This in relation to the Noise requirements is going to be extremely difficult to meet as we then have inexperienced under qualified officials deciding on what is and what is not acceptable. The courts are already experiencing a major problem with each case and specialist expert witnesses are effectively deciding the cases.
The standards have been drawn up and accepted. –
SANS 10103 –2004 – The Measurement and rating of environmental noise with respect to land use, health, annoyance and to speech communications.
5.6 Classification of Districts
The new standard outlines various districts and then indicates an acceptable Equivalent Continuous Rating Level (L Req T) for noise in each.

5.7 Old or New Regulations
With the NEMAQA enacted in Parliament it is already technically in force but as the minister has indicated that the act will only be enforceable from 2007, the older Provincial Noise Regulations are still applicable with these dictating that a company or undertaking may not contribute more than 7,0 dBA to the background or ambient noise level applicable.
Enforcement of the Provincial regulations have also proved to be increasingly onerous as these are complicated further by provisions within the Constitution which dictate that all citizens have a right to acceptable conditions (which includes noise.)

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Air Pollution and Health Effects in Children

Download and read this PDF article.

If this article is not available anymore it can be requested.


Chris Loans

Air Pollution Study – PM2.5

A great Air Pollution Study presentation, easy to follow and interpret.