What is a dust screen in construction?

A dust screen is a temporary barrier used on construction sites to contain dust and debris generated during construction activities. Dust screens are an important tool for managing dust, which can cause respiratory issues for workers and neighbors if left uncontrolled. Installing dust screens is a common requirement on many construction projects today.

Why are dust screens used in construction?

There are several important reasons dust screens are utilized on construction sites:

• Reduce dust migration – Dust screens contain dust and debris, preventing it from blowing onto neighboring properties or creating a nuisance.
• Protect air quality – Dust screens help control the spread of particulate matter that can cause respiratory irritation. This protects the air quality for workers and nearby residents/businesses.
• Safety compliance – Many local regulations require dust screens as part of overall dust control plans for construction sites, especially in urban areas.
• Avoid runoff contamination – Dust screens prevent debris and sediment from washing off sites during rain/storms, keeping it from polluting nearby waterways.
• Improve visibility – Screens improve visibility around the site by reducing airborne dust.

In summary, proper use of dust screens is critical for managing environmental and safety issues on construction projects.

When are dust screens required?

There are several situations that typically require dust screens on construction sites:

• Demolition activities – Any demolition of existing structures requires dust screens to contain airborne particles.
• Excavation and earthwork – Dust screens are needed during digging, trenching, grading, or any disturbance of soils.
• Concrete work – Sawing, drilling, sanding, or any concrete work generates concrete dust requiring screens.
• Sandblasting operations – Sandblasting produces large amounts of hazardous dust that must be contained.
• Working near occupied areas – If the site borders homes, businesses, or pedestrian areas, screens are vital.
• Dry and windy conditions – Extra dust control is needed on dry, windy days to prevent dust from blowing away from the site.
• Required by regulations – Local laws often mandate dust screens around the perimeter when working in urban areas.

Project managers should evaluate the specific site conditions and scope of work to determine where dust screens are warranted. The local municipality may also mandate dust screens through permit requirements.

What are dust screens made of?

There are a few common materials used to construct dust screens on construction sites:

• Plastic sheeting – Plastic sheets, such as polyethylene, are a popular choice. The sheets are durable and easy to install on temporary fencing. Plastic sheeting comes in various thicknesses, such as 2-mil, 4-mil or 6-mil.
• Mesh/netting – Mesh screen materials like nylon, polypropylene or polyethylene are frequently used. The openings in the mesh allow some air/moisture flow while blocking dust particles.
• Insulation blankets – Dense synthetic insulation blankets can contain dust when hung on fencing. This is a self-supporting material that does not require other framing.
• Wood/plywood – Plywood, OSB or solid wooden boards provide a sturdy, opaque dust barrier option.

The location, expected weather conditions, duration of the project and local codes will determine which dust screen material is most suitable.

What are the different types of dust screens?

There are several basic types of dust screens used on construction sites:

Perimeter Screens

• Installed around full perimeter of site, attached to fencing or scaffolding.
• Keeps dust from migrating off-site and provides visual screening.
• Can be left in place for duration of project or moved as needed.

Mobile Screens

• Portable screens mounted on movable frames with wheels.
• Allow screens to be repositioned as needed during different stages of work.
• Provide flexible dust control options for contractors.

Enclosure Screens

• Wrap fully around specific operations generating dust such as concrete sawing or demolition.
• Creates contained work area to capture dust at source.
• Uses zippered access points to allow entry and exit while containing dust.

Scaffold Sheeting

• Heavy fire-retardant polyethylene sheets attached to scaffolding or frames.
• Provides full-height containment around scaffolding work zones.
• Well-suited to demolition and abrasive blasting applications.

The combination of different screen types utilized will depend on the site layout and phasing of construction activities.

What height should dust screens be?

Recommended dust screen height is typically as follows:

• Perimeter screens – Minimum 8-10 ft height is preferred. Full height up to top of fencing may be warranted for sites bordering sensitive neighbours.
• Mobile screens – Minimum 8-10 ft but can be taller depending on equipment heights and how close screens will be positioned next to work.
• Enclosures – Screens should be full height of operation being enclosed, such as scaffolding height.

Screens should be high enough so dust cannot blow over the top. Local regulators may mandate specific minimum screen heights.

How should dust screens be installed and supported?

Proper installation is key to keep screens securely in place. Here are common methods:

• Perimeter fencing – Attaching screen materials or mesh directly to temporary fencing with zip ties, hooks, wood/plastic slats or other fasteners.
• Freestanding frames – Screens can be mounted on movable frames of lumber, steel pipes or scaffolding.
• Scaffolding – Screens are installed on exterior side of scaffolding, often with wood ledgers bolted through uprights to attach screen clamps.
• Cables – Screens hung from cables strung between poles or scaffolding and tensioned tight.
• Adhesive – Foam adhesive strips can adhere sheeting directly to walls/fencing without penetrating fasteners.

Screens should be installed flush against fence lines or braced structures without gaps. Allowing the screen material to flap or billow decreases dust control effectiveness.

What maintenance is required for dust screens?

To maintain proper dust control, screens require periodic inspection and maintenance:

• Tears or holes in screen materials should be repaired or patched to prevent dust escaping.
• Keep screens clear of accumulated dirt/mud which can weigh down and sag the barrier.
• Check screen attachments are secure, adjusting tension on ties, clamps or cables as needed.
• Monitor screens for wind or storm damage, making repairs as soon as feasible.
• Remove dust buildup by sweeping or vacuuming screens regularly.
• Watch for gaps at edges, overlapped seams or zippered accesses and seal up any openings letting dust through.

It is good practice to include screen inspection and maintenance in site housekeeping plans and safety meeting topics.

How long can dust screens remain installed?

Dust screen duration depends on the project schedule and type of screen:

• Perimeter screens – May remain for the entire project duration if properly maintained.
• Mobile screens – Moved to various locations for shorter durations of days or weeks.
• Enclosures – Used for single dust-generating task then removed, such as a localized demolition.

Consider the longevity of the screen material itself when determining estimated useful life. Plastic sheeting, for example, becomes more prone to tearing over time.

Do dust screens require specialized equipment?

Simple hand tools are typically all that is needed for installation and maintenance:

• Screw guns, drills, sledgehammers to erect screen frames or scaffolding.
• Cable cutters, utility knives, scissors to cut screen material to size.
• Zip ties, carabiners, tape to fasten material to frames or fencing.
• Ladders for accessing taller screens.
• Poles with hooked blades to reach high screens when repairing tears.

Larger sites may utilize specialized dust screen installation equipment like hydraulic manlifts, telehandlers or tensioning devices to speed up installation and servicing. But hand installation is common for many residential projects.

Should dust screens be reused or recycled?

If dust screens remain in good condition after use, reuse may be possible in many cases:

• Plastic sheeting can potentially be taken down, folded, transported and reinstalled at a new site, assuming it has retained integrity.
• Mesh netting or blankets that are undamaged can also be reused on subsequent projects.
• Treated plywood sheets may also be reusable after cleaning both sides.

Reusing screens when possible reduces costs and construction waste. However, heavily soiled or torn screens that cannot effectively control dust should be disposed of properly. Many common screen materials like plastic, wood, and poly mesh can be recycled rather than landfilled when their use life has ended.

Are there any alternatives to dust screens?

While screens are the most common approach, some other dust control methods can supplement or replace screens in certain applications:

• Water spray – Misting work areas with hoses or sprinklers is very effective for dust suppression but requires access to water.
• Foam suppressants – Applying foaming agents onto surfaces prevents fine particles from becoming airborne.
• Vacuum shrouds – Containing dust at the source by vacuuming it as it is generated, such as with handheld concrete saws.
• Wheel wash – Stopping dust carryout from vehicles leaving site protects nearby streets.
• Air filters – Localized exhaust ventilation with HEPA filters for contained areas.

These alternative controls are often used to supplement perimeter screens. But full enclosure screens provide the highest level of dust control for many construction activities.

Conclusion

Dust screens are vital, multifunctional tools for controlling dust and debris on construction projects. Proper use of perimeter screens, enclosures, mobile barriers and scaffold sheeting reduces environmental impacts, improves air quality and protects workers and the public from nuisance dust. With careful installation, maintenance and planned dismantling and recycling, screens provide an economical and efficient means of dust management across a wide range of construction operations.