Potable Water Tank Coating

Dr. P Phillips Hospital – Orlando Florida | Contracted By Harper, a Limbach Holdings, Inc.

Harper, a Limbach Holdings, Inc. contracted Industrial Painting Solutions to sandblast and re-coat two potable water tanks for the Dr. P Phillips Hospital in Orlando, Florida. Harper is a nationwide general contractor that delivers and maintains quality building systems, focusing specifically on MEP+C-intensive projects for building owners and contractors. Harper manages all components of mechanical, electrical, plumbing and control systems.

Blast Containment of Potable Water Tanks

The scope of work for this project was to set up blast containment inside the control room where the tanks were stationed. The tanks were roughly 6400 gallons each. The interior lining of these tanks was failing due to poor preparation from the previous painting contractor. Paint chips had peeled off leaving the substrate exposed to water and the environment. Substantial rust had formed inside the tanks and was not suitable for potable water.

Challenging Environment For Sandblasting & Painting

This job had a number of challenges. The main challenge was the location of these tanks were in close proximity to patients and the hospital staff. Full containment of dust and paint were mandatory at all times. Even a small amount of dust or paint fumes would put patients in danger of exposure. A 600 CFM portable dust collector accompanied by a 70 KW generator was used to fully contain the job. The next challenge was the location. The tanks were in an enclosed building with plumbing, with only one entry and exit. Navigating in and out of the structure was difficult with paint lines, dust collector chutes and sandblast hoses. The final challenge was the internal height of the tanks. Each tank was roughly 12-13’ tall, so blasting and painting from the bottom of the tank were not possible. Scaffolding was brought in piece by piece and then each piece had to be navigated through a 24” manway hole and erected in place.

Potable Water Epoxy

The scope of work was to remove the existing coating to an SSPC6. This removes all paint, rust and other material. Once a 1-2 mil profile was achieved, all media was removed by the dust collector and vacuums. Once clean, one full coat of Macropoxy 646 PW at 3-5 mils DFT was applied. A stripe coat was applied by roller to all seams, angles, and welds. Lastly, a third coat was applied with 3-5 mils DFT of Light blue Macropoxy 646 PW potable water epoxy. 646 PW is a high solid, high build, fast drying, polyamide epoxy classified by UL to ANSI/NSF 61as a tank lining for potable water storage tanks.