Our Staff


John Barnett

John E. Barnett (President) has over thirty years of marketing and management experience in the construction, environmental and laboratory industries. Mr. Barnett joined QuanTEM 20 years ago and through diligent focus on growth has built QuanTEM into the premier testing laboratory it is today. His successes at QuanTEM include expansion of laboratory services to include most Indoor Environmental Quality concerns, promoting training courses for the education of environmental professionals, and insisting on excellent customer service throughout the organization. His varied experience includes hazardous materials site testing, assessment, and remediation, business ownership and executive level business management.

Ingrid Gumbs-Diaz, Resource Development Specialist

Yomi Ajibode

Ingrid Gumbs-Diaz (Resource Development Specialist) joined QuanTEM in June of 2014. She has 12 years of experience in sales and marketing, as well as over 6 years of experience in laboratory bench work. She has a degree in Biochemistry from Oklahoma State University and a Master’s in Business Administration from Oklahoma City University. She is originally from San Juan, Puerto Rico. Her passion for science and business has put her in a position to establish beneficial and long lasting relationships with existing as well as potential clients wherever she goes. She has been in the soda industry, meat industry, as well as biochemistry and environmental quality lab service industry.

Ingrid brings to QuanTEM an approach of reinventing customer relationships, and innovation, making them a part of the QuanTEM family. Customers receive more than just lab results when working with her and the lab team. They enjoy a great partnership, a sincere concern for their business, and customized service to help them succeed.


Jeff Mledush

Jeff Mlekush (Vice President) has over fourteen years of experience in asbestos, lead, industrial hygiene and indoor air quality. He joined QuanTEM in March 2000. He has a Geology degree from the University of New Mexico and a Master of Business Administration from Oklahoma Christian University. Prior to joining QuanTEM Laboratories, Mr. Mlekush was the Senior Project Manager for Acme Environmental, Inc., an environmental training and consulting firm in Albuquerque, New Mexico. He was also the Asbestos/Industrial Hygiene Manager for Assaigai Analytical Laboratories, Inc., an analytical laboratory and industrial hygiene firm in New Mexico and Texas.


Steven Karr

Steven Karr (Accounting Manager) joined the QuanTEM team in May of 2012. He has a degree in accounting from the University of Central Oklahoma and is currently pursuing a Master's in Business Administration. Prior to coming to QuanTEM Steven has 20 years' experience in accounting and business operations.