Dust control is a must for industries which produce high volumes of dust such as construction and mining. Not only are wind fences used to reduce product loss due to erosion, they are often an occupational health and safety requirement due to the problematic nature of fine dust particles on windy days. With many dust particles being sub 10-microns (PM10’s), it’s extremely important that you make every effort to reduce the risk of respiratory distress in your workers – which can cause much bigger problems down the line.
There are many products on the market designed to limit the amount of dust that blows across a worksite. Some of these include fog canons, water mist canons, water sprays, wind fences and wind breaks.
What is a Wind Fence?
A wind fence is a large fabric barrier that can be installed up to 30 meters (100 feet) tall. They can be manufactured with various types of fabric depending on the size of the site and individual requirements and budget.
To be effective, wind fences must be installed upwind and downwind of your site, in order to slow the wind and its strength by deflecting it away.
Types of Fugitive Dust
The term ‘fugitive dust’ refers to particulate that is lifted into the air either by man-made or natural activities in large open areas. Fugitive dust tends to come from two distinct sources:
- Eroded dust
This is where particles are swept off the ground or a pile of product (for example, fine sawdust). This type of erosion is highly sensitive to wind speed. Wind fences are very effective in these scenarios and in some cases, wind speed can be reduced by 50%, decreasing dust distribution to 1/8th. This is the difference between losing 2000 pounds of product per month compared to less than 250 pounds.
- Airborne dust
Airborne dust involves particles falling from a conveyor or being kicked up and distributed into the air by machinery. Utilizing a wind fence in this situation would cut wind speed of the affected area in half.
Why Are Wind Breaks Important?
The key objective of any dust control strategy concerning wind is to reduce its speed.
Wind fences control the amount of wind blowing across your worksite and allow minimal invasion of your product and clouds of harmful dust. This is achieved by producing a zone behind the wind fence which aims to slow wind to about a quarter of its natural speed.
For example, a 50ft tall windbreak will extend the zone by about 250ft downwind. From 250ft to 500ft, the wind speed will increase up to about half that of the incoming wind. Beyond that, wind speeds increase quickly.
Another advantage of wind breaks is their low level of maintenance – once installed they require no power, cleaning, or daily upkeep and will continue operating around the clock.
They are also environmentally friendly as they don’t consume oil, gas, electricity or water.
Wind breaks can be beneficial in a number of scenarios including:
- Debris and garbage handling areas
- Control of waves and turbulence on ponds
- Snow deflection and control
- Fencing and privacy
- Wind deflection for air cooling towers