Dust Control and Ventilation for Basement Shotcreting Works

Project Overview

At a major commercial construction project, shotcreting works were being carried out inside a multi-level basement excavation to stabilise retaining walls and structural elements. The spraying process generates fine airborne dust as concrete is applied at high velocity and rebound material breaks apart, which can quickly accumulate in enclosed spaces with limited natural airflow. As the shortcrete mix contains silica, maintaining safe air quality for workers in the basement was critical.

The project team was provided with a customised ventilation and dust extraction solution to maintain continuous, clear airflow in the work zone, while capturing airborne dust.

Challenge

Our construction client was carrying out shotcreting works in the basement of a major building project. Shotcrete was being applied to structural and retaining walls within the excavation, several levels below ground.

While shotcreting is a common technique in civil and structural construction, the process generates significant volumes of airborne dust. As the concrete is sprayed at high velocity, fine particles become suspended in the air – particularly when rebound material breaks apart during application.

In open environments this dust can disperse quickly. However, in a basement with limited natural airflow, airborne dust can build up rapidly and remain in workers’ breathing zones.

A key concern was respirable silica dust (a leading cause of silicosis, COPD, lung cancer, and other occupational lung diseases) contained within the shotcrete mix. Without adequate dust control and ventilation, workers operating in the basement could be exposed to elevated dust concentrations during spraying operations.

The client needed a practical solution that would:

• Maintain safe air quality for workers in a basement environment
• Control airborne dust generated during shotcreting
• Provide continuous airflow to prevent dust accumulation
• Support safe working conditions throughout the construction phase

Solution

To manage dust and maintain airflow within the basement, an engineered dust extraction system and ventilation system were implemented.

Shotcrete dust was captured by high-powered DUSTEX® Raptor Pro extraction systems, with capture hoods placed at the shotcreting activity (spraying). This saw airborne particles immediately captured (with negative pressure), contained and controlled in the unit – away from workers’ lungs.

High-capacity VENTEX® 300 centrifugal fans were positioned at ground level, supplying fresh air into the basement through heavy-duty ventilation ducting. This created a steady airflow through the work area.

By positioning the fans at ground level and ducting air down to the basement, the system could operate continuously without interfering with construction activities.

Outcome

The extraction and ventilation setup created a controlled airflow environment within the basement during the shotcreting works.

This approach helped to:

• Reduce airborne dust levels in the work area
• Maintain fresh airflow for crews operating below ground
• Improve visibility during spraying operations
• Support safer working conditions throughout the project

With the combination of dust extraction, centrifugal ventilation fans and ducted airflow, the project team was able to continue shotcreting operations in a basement environment while effectively managing dust generated during the process.