As New Zealand becomes hotter and drier, the need for effective dust management has never been greater. Dust is no longer something a hose-down deals with at the end of the day. It is a health issue, a machinery issue, a visibility issue and a compliance issue, and it does not stop at the site boundary.
A drier country makes dust a bigger problem
Rainfall has always been a natural form of dust suppression, to a certain extent. That safety net is thinning. Our summers are increasingly arid, and climate change is protracting dry seasons as less rain falls across the year. The less you can count on rain to settle a yard, the more you have to settle it yourself, which is why systems like transportable dust suppression units have moved from useful to necessary. Couple this with the expansion of New Zealand's urban areas, complete with impermeable structures replacing vegetation and natural surfaces, and you have even more reason to prioritise dust control.
Where the dust actually comes from
Dust management has always been critical, even if you set aside the changing climate and urban sprawl. Airborne dust arises from many sources: civil sites such as ports, forests and road works, construction sites, agricultural and horticultural activities, vehicle movements on sealed or unsealed roads and yards, and mining and mineral extraction. The common thread is disturbed ground and things moving across it. As regulations and resource consents become more stringent, dust management is necessary in all of these settings. Regardless of the source, dust has to be controlled for our health, for safety at work, and for the environment.
Dust hides what people need to see
When dust becomes airborne it has several effects, and the most immediate is that it takes away visibility. That is a particular concern for traffic navigating through roading projects, where the public is moving at speed through a live work site and the margin for a misjudgement is small. Visibility loss is also the effect that arrives fastest. A yard can go from clear to obscured in the time it takes one truck to cross it, which is why control has to be built into the daily operation of a site rather than called for once conditions have already deteriorated.
Dust wears machinery down
Dust also adversely impacts the effective operation of machinery. Fine particles infiltrate small components and, over time, bring them to a halt without regular maintenance. There is a trap in that sentence worth drawing out: the maintenance is the cost either way. Either the dust stops the machine, or the servicing needed to keep the dust from stopping the machine takes it out of action anyway. Both outcomes are downtime. Controlling dust at the source is the only version of this where the machine stays working, which is what makes suppression an operating decision rather than a housekeeping one.
The health case is the serious one
Dust can have direct health effects due to biologically active materials. As an extreme case, some mineral dusts with silica can cause a lung disease known as silicosis when present in high levels. A little less alarming but still unwelcome are alkaline dusts that irritate the eyes. Other types of dust may contain toxic metals such as mercury or lead, or even traces of asbestos, which was widely used in New Zealand not so long ago. Compost dust contains soil microbes, allergens and pathogens, including legionella. Housing developments and their associated infrastructure disturb natural vegetation, releasing pollens and similar organic allergens that hay fever sufferers know all too well.
Dust does not stay on site
Considering those examples, it is fair to say that dust management, regardless of type or source, is a responsibility to be taken more seriously than ever. It has to be seen in the light of compliance around work sites and an obligation to protect both the people working on site and the general public. That second group is easy to forget, and it should not be. Dust travels a long, long way. Ask the people of Hawkes Bay, who watched clouds of dry silt travel several kilometres in the aftermath of Cyclone Gabrielle. You do not necessarily have to be on site to be affected by what a site puts into the air.
What a modern suppression unit needs to do
Keeping the dust down now requires more than the occasional hose-down. Well-designed dust suppression units, with features that support operator safety and effectiveness, are vital. Promax slip-on units are relatively easy to mount to the tray of a truck, and a range of tank capacities makes it just as simple to match a unit to the vehicle's size. In-cab controls keep the operator well away from a dusty and potentially dangerous worksite. High-quality components such as tanks, pumps, hoses and galvanised steel pipework combine for reliable ongoing operation. Fast bulk water transfer, hydrant filling, and ball baffle systems that deflect fluid surge movement during transportation should be considered standard.
Matching the unit to the work
The best dust suppression methods provide the most effective control in a dusty country, and one that is getting dustier. What that looks like in practice depends on the site. A unit that spends its day on sealed roads has a different duty cycle from one working an unsealed yard or a mineral extraction face, and the tank capacity that suits a small truck will not suit a large one. Because these units are built around transport tanks carried on a moving vehicle, how the tank behaves when the truck is moving matters as much as how much it holds.
Talk to the civil team
This summer, as dust levels are expected to rise, consider Promax Liquid Management Solutions as your ally in maintaining a clean and safe environment. Whether you are working on a construction project, managing an agricultural operation, or you simply need a solution for dust control, we have got you covered. Our civil sector team can work through duty cycle, tank capacity and vehicle fit with you, and if urban development and hard surfaces are part of your picture, our work on managing impermeable surface issues covers the other half of that story. Get in touch with the team to talk it through.