Arc Flash & Containment Assessment — Brisbane Hospital

Overview

A Brisbane hospital was upgrading its high voltage electrical infrastructure, installing a new transformer and 11kV ring main unit (RMU) as part of the works. The RMU was being installed within a dedicated indoor plant room — a configuration that introduced specific challenges around arc fault energy and the consequences of a fault event within an enclosed space.

The hospital engaged Grid Dynamics to carry out an arc flash assessment and an arc fault containment study for the new installation. Given the critical nature of hospital infrastructure and the indoor location of the equipment, it was essential that the engineering properly addressed arc fault risk — both for personnel safety and to ensure the installation met the relevant building and safety standards.

Scope of Work

• Arc flash assessment for the new transformer and 11kV RMU installation, determining incident energy levels and arc flash boundaries
• Arc fault containment study assessing the behaviour of arc fault energy within the indoor plant room
• Analysis of venting requirements — determining how arc fault gases and pressure would need to be managed during a fault event
• Review of room geometry and construction relative to containment requirements
• Recommendations for venting design and any other measures required to ensure safe containment of a fault event
• Preparation of engineering documentation suitable for RPEQ sign-off

Outcome

The study provided the hospital and its project team with a clear, engineered solution for managing arc fault risk within the indoor installation. The venting requirements were defined, and the containment approach was documented in a form suitable for use by the building and electrical contractors during construction.

The completed studies gave the project team confidence that the installation had been properly assessed and that the design adequately managed the risks associated with high voltage equipment in an occupied building.