Day & Zimmermann is the nation’s leading provider of maintenance and modifications services to the U.S. power industry helping coal-fired and natural gas plant owners generate power.

What We Do

Maintenance & Modifications

Our Total Accountability Model provides a single point of contact driving accountability across safety, human performance, cost, schedule, quality, and resource supply.

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Projects & Construction

Our teams are familiar with, and have worked on, virtually every primary and secondary plant system in both outage and non-outage environments, routinely executing critical and near-critical path work scopes.

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Condenser Services

As the largest condenser retubing contractor in the United States, we bring innovative and cost-effective services using the most advance methods, tooling, and equipment in the industry.

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Valve Services

Our full-scope capabilities are an integrated approach, including valve and operator testing, repair, and refurbishment.

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From scaffolding design to decontamination and storage, our planning and implementation process is designed to reduce or consolidate scaffold use.

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Professional Technical Services

The Professional Technical Staffing business line specializes in providing cost-competitive workforce solutions to the power, process, and industrial markets.

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Fossil Fuels

Approximately 66% of all US energy is generated by fossil fuels.

Emissions from coal-based electricity generation have decreased by more than 40% since the 1970s while coal use in the U.S. has tripled.

The coal industry provides more than $1 billion in total U.S. labor income.