Roy Bartholomew Sonora CA

Director of Engineering for On Guard Security Systems Inc.

About Me

In Modesto, California, Roy Bartholomew (Roy Bartholomew Sonora) is the Director of Engineering at On Guard Security Systems, Inc. Mr. Bartholomew was born and reared in the San Francisco Bay Area, the youngest of seven children born to French-speaking Cajun parents.

Roy Bartholomew is also the owner of By Referral Only Electric. After 35 years in engineering, he has amassed a specialized and in-demand skill set and beneficial relationships with local and national company owners.

Mr. Bartholomew's engineering, design work, and consulting services for Biodomes and other engineered ecosystems are well recognized in the engineering world, in addition to his full-time profession and entrepreneurial endeavours. Mr. Bartholomew currently resides in Northern California with his wife and children.

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Roy Bartholomew Sonora CA - Portfolio

Recent News

Roy Bartholomew Sonora CA
September 21, 2023

A Voyage Through the Biodôme’s Diverse Habitats

Montreal’s Biodôme is a testament to the marvels of Earth’s biodiversity, conveniently located under a single roof. A unique structure repurposed from the 1976 Olympic Games’ velodrome, the Biodôme today offers a tantalizing glimpse into a world where ecosystems are preserved, studied, and celebrated. Here’s an overview of the awaited wondrous environments for those yet […]

September 7, 2023

Engineering Marvels: Unraveling the Purpose and Importance of Biodomes

Biodomes, often called ecological domes or living environments under glass, have captured the imagination of engineers and environmental enthusiasts alike. These extraordinary structures encapsulate diverse ecosystems within their transparent walls, providing a controlled environment where nature thrives. But what drives engineers to create biodomes, and why are they so essential in today’s world? In this […]

Roy Bartholomew Sonora CA
August 25, 2023

The Cost of Electrical Certification in California: What You Need to Know

In California, electrical certification is vital for individuals seeking a career in the electrical industry. Whether you are an aspiring electrician or a seasoned professional looking to expand your expertise, understanding the cost of electrical certification is a crucial step in your career journey. The expenses associated with obtaining electrical certification can vary based on […]

August 10, 2023

Unveiling the Benefits of Biodomes

Unveiling the Benefits of Biodomes, innovative solutions that bridge the gap between technology and nature are gaining traction in an era marked by environmental challenges and a growing concern for sustainability. One such solution that stands out is the concept of biodomes. Biodomes, or geodesic domes or biomes, are enclosed ecosystems replicating natural habitats and […]

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