Dust is not just a nuisance – It is a real threat to your health.
Working on construction and demolition sites can leave you exposed to harmful levels of dust and fine particles. Fine and ultra-fine particles which behave almost like gases; will leave construction sites and can contribute to community urban pollution; which is a problem for everyone. These particles are referred to as PM (Particulate Matter) and it is these particles that are of a concern in urban areas as they often reach undesirable levels causing well documented adverse health concerns.
Controlling dust emissions on site is important, as is dust monitoring to evaluating the effectiveness of control measures.
Dust control measures:
· Water suppression is effective at reducing site dust emissions
· Use on tool extraction of dust systems where possible.
· Reduce cutting on site by ordering raw materials in suitable sizes.
· Producing a demolition plan and selecting equipment to minimise dust events on site. Sheeting and screening should be used wherever possible.
How To Monitor Construction Dust and Particulates
A routine visual inspection at the boundary of the site, and at properties in the near vicinity should be considered the minimum requirement for construction dust monitoring. This information should be noted and stored with the weather conditions including wind direction. Typical locations to observe this visual dust are:
· Car Bonnets and roofs
· Windows and windowsills
· Permanent Street furniture such as telephone boxes, benches, and street lighting etc.
Passive measurement devices
These are devices which require no power and can collect dust samples at the boundary of the construction site. They usually require frequent site visits, typically once a week, to change samples and to send the collected dust pads for analysis. Passive dust collection is usually categorized as two types of devices:
· Dust flux – Directional properties (where did the dust come from)
· Dust deposition gauge – Deposited dust (how much dust)
Figure 1 -Deposition dust gauge (L) Dust Flux (R)
Advantages – Low cost to purchase, can provide directional data, dust samples can be sent for analysis to establish content of dust.
Disadvantages – Expensive to run with frequent site visits required. Averaged data only – no history of dust emission against time, so it is not possible to identify dust events. Not real time and no alerts possible. Primarily for nuisance dust – not fine particles which are most harmful to health.
Other solutions: Real time dust monitors
These monitors work by pumping sample air through a controlled space and using a laser to count particles in the air. They usually have a built-in heater on the inlet to dry the sample air which is important to measure accurately and to remove false positives, which can be generated by fog and high humidity.
These monitors can sample quickly and store data minute by minute. This provides useful information for controlling dust and particulates at construction sites, as events can be identified quickly, and you can be alerted straight away via email/SMS. Dust limits are typically set over a period of 15 minutes to identify local site-specific dust events.
Advantages – Automated and infrequent site visits required. Real time with alerts. Minute by minute data for analysis of dust emissions by time, accessed remotely on any device. Measures nuisance dust and harmful fine particles.
Disadvantages – Relatively expensive to purchase. Requires external power.
Campbell Associates provide the fully automated Dust Sentry and the Dust Profiler for sale or hire. The PM10 part of the Dust Sentry is MCERTS by the Environmental Agency and will give you accurate readings to control your sites emissions. The Dust Profiler can measure TSP, PM1, PM2.5 and PM10 simultaneously. You can also add gas measurements in parallel to these systems for NO2, Ozone and VOC.
If you want to learn more, please contact us.