Background

Nuclear generating stations are consistently evaluating the safety of their grounds and equipment. In July 2019, a company in Michigan was concerned that the station’s boiling water reactor (BWR), Unit 2, had potential safety risks due to paint deterioration in the power suppression pool (torus).

Client Needs

The emergency core cooling pipes in a BWR cannot perform their main function if too much debris has accumulated. Over time, the high speeds of the water in the torus can tear some of the insulation from pipes, scrape coating from the walls, or create other forms of particulate in the water. Per NRC requirements, Unit 2 had already installed large strainers to combat potential blockage; however the NRC wanted to examine the equipment’s design to ensure the system wouldn’t be overwhelmed if more debris accrued than predicted.

Resolution

In response to their findings, the company is draining, sandblasting, and repainting the nearly 10,000 pounds of coating protecting the torus from rust and other forms of degradation. The confined space will be drained of water during the project, and the air will be full of particulate as the existing paint is removed from the interior walls. To confirm the new coating is consistently applied, the organization needed a lighting solution that would illuminate the entirety of the space. If the materials are not administered correctly, the project will have to be repeated sooner than anticipated. The company also needed a durable product that can survive a hazardous, confined space environment.

Before purchasing supplies for the coating reapplication, an explosionproof Ericson 1007 Series Hazardous Location High Bay Light was evaluated, which provided a bright 21,000 lumen output. Satisfied with the product’s performance, the company utilized a total of 36 of the 1007 Series to light the 250 foot circumference torus for the duration of the project.