Our History

Founded on August 5, 2005

AEI Corporation was founded on August 5, 2005 by John Schumacher, Dennis Shelp, and John (Jay) Freeman in Denver, CO. The staff also included Zach Jason (now Partner), and Kristin Tittle.

John L. Schumacher – President & Founder

Mr. Schumacher is a founder of AEI and has been a consulting and forensic engineer since 1992. He is a licensed chemical engineer and an IAAI Certified Fire Investigator who specializes in determining the origin and cause of fires, flash fires, and explosions; investigating accidents in the chemical process and oil & gas industries; analyzing flammable and combustible liquid, combustible dust, reactive chemical, self-heating, and chemical-related accidents; and investigating carbon monoxide incidents. He is the current President of AEI.

Dennis E. Shelp – Vice President & Founder

Mr. Shelp is one of the founders of AEI.  He is a mechanical engineer, a Certified Fire and Explosion Investigator, and has performed forensic investigations since 1997. He specializes in the investigation of fires, explosions, and mechanical equipment related incidents. He has presented at local and national conferences and seminars and has provided expert testimony in numerous state courts. Mr. Shelp is the Vice President of AEI Corporation.

John (Jay) Freeman – Founder Emeritus

One of AEI's original founders, Mr. Freeman brought over 48 years of forensic experience to the table and was nationally recognized for his specialization in gas appliances and natural gas and propane explosions.

Staff Photo 2006

AEI's staff in 2006 was comprised of Jay Freeman, John Schumacher, Dennis Shelp, Zach Jason, and Kristin Tittle.

Laboratory Facility at AEI’s Jasmine Location in Use

Forensic engineering laboratories play a critical role in uncovering the causes of failures in structures, systems, and materials. Testing at AEI's original labs located on Jasmine Street in Denver, is shown here.

AEI’s Staff Grows in 2007

AEI adds Robert Witter (Electrical), David Burnett (Civil/Structural), and Gary Oberg (Technician) to the team.  Shown in photo: Zach Jason, John Schumacher, Robert Witter, Kristin Tittle, Gary Oberg, Dennis Shelp, and Jay Freeman.

2008 AEI Team

Business support is bolstered with the addition of Dina Schendzielos. Shown in photo: Gary Oberg, Jay Freeman, Dina Schendzielos, Dave Burnett, Dennis Shelp, John Schumacher, Kristin Tittle, Zach Jason, Robert Witter.

Charles (Charlie) Sullivan, ASCR2, CKH2

In 2009, Charles Sullivan joins AEI. Mr. Sullivan is an expert in the layout/design, installation, inspection, testing, maintenance, repair, and operation of fire suppression systems and their components, and often addresses industry standard of care issues.

Carol Chavez Joins AEI

Carol Chavez joins the AEI family. Ms. Chavez brings a powerful blend of executive leadership, financial strategy, and operational excellence to the firm. Before joining AEI, Carol led iniatives in computer-aided dispatch, weather telemetry systems, and public sector services. Carol provides strategic planning and financial oversight to the firm, as well as marketing leadership, sales operations, contract negotiation, and executive management.

AEI Moves to New Facility in Littleton, CO

Following a full remodel and addition to AEI's new headquarters, AEI adds state-of-the-art laboratory capabilities and a two acre lot to allow for better ability to conduct outdoor, full-scale testing.

AEI’s 2011 Team

Shown here: Dan Sadler, Brent Fakuda, Carol Chavez, Gary Oberg, Charles Sullivan, David Burnett, Donna Sprinkle, Mike Brown, John Schumacher, Jay Freeman, Dennis Shelp, and Zach Jason

Laboratory Facility at AEI’s Brandon Drive Location in Use

The move to Littleton, CO gave AEI the ability to facilitate and conduct large laboratory inspections. AEI has the right equipment to complete both demonstrative and non-destructive testing, including a Keyence microscope, FTIR, hood system, X-Ray, and much more.

AEI 2012 Charity Casino Night

In 2012, AEI hosted it's first Casino Charity night at their Littleton facility.  Proceeds from the event benefited the Second Wind Fund of Metro Denver whose mission is to decrease the incidence of teen suicide by removing financial & social barriers to treatment for at-risk youth.

Fire Alarm Control Panel Expertise

Charlie Sullivan discusses fire alarm control panels and safety at AEI's Hood Seminar in Summer of 2012.

2nd Annual Charity Event

In 2013, AEI hosted its 2nd Charity Casino Night and Silent Auction.  The proceeds from the event went to The Delores Project, a metro-Denver charity that provides shelter, hope, and direction to local homeless women.

AEI’s 2013 Team

Dan Sadler, Cameron Novak, Todd Hedglin, Zach Jason, Donna Sprinkle, Brenda Johnson, Gary Oberg, Charlie Sullivan, Carol Chavez, Brent Fakuda, Dave Burnett, John Schumacher, Jay Freeman, and Dennis Shelp

Flashover Friday’s Event at AEI

AEI Corporation conducted the inaugural Flashover Fridays event on June 27, 2014. Several attorneys, insurance industry professionals, and first responders attended to learn about fire behavior first-hand. The inaugural burn simulated a type of fire that occurs all too often, kitchen fires caused by unattended cooking oil left on a stove top.

AEI Hosts 3rd Annual Charity Event

AEI hosts it's 3rd Annual Charity Casino Night and Silent Auction.  This year, raising $6,000 for the Angel Eyes Child Loss Awareness Organization whose mission is to provide free, professional grief support to families facing the devastating loss of a pregnancy, infant, or young child.

Just in Time for Christmas

AEI's Flashover Friday's demonstration highlighted the dangers associated with Christmas trees if not properly maintained and allowed to dry out.  The demonstration separated a burn cell into two quadrants to demonstrate the difference in the veracity and duration of the fire with and without a sprinkler system.

Jeff Berino Joins AEI

In 2015, AEI gained the incredible talent and insight of Jeff Bernio. Jeff is well known for his many years of experience in wildfire investigations for government agencies and utility companies in the United States, Canada, and Mexico. He also has expertise in fire scene incident management and senior level instruction for leadership and fire science classes.

Dr. Shawn Sapp

Shawn joins AEI as a Materials Scientist. Dr. Sapp has been a practicing materials scientist and analytical chemist since 2002. He is American Society of Metals (ASM) Certified in fracture mechanics, fractography, and failure analysis to determine the origin and cause of failures in metals, ceramics, plastics, and composites.

Flashover Friday’s, “All Up In Your Grill”

This burn simulated a gas grill fire on a patio and possible extension into a dwelling.  A scenario was created where the grill caught fire due to a defective seal on the valve on the propane cylinder.

AEI Hosts 4th Annual Charity Event

AEI keeps the tradition going, hosting its 4th Annual Charity Casino Night and Silent Auction.  The proceeds from this event went to The Adoption Exchange, a not-for-profit organization working on behalf of children in the foster care system.

AEI Flashover Friday’s, CSST Arcing

AEI hosts a Flashover Friday's event at its Littleton Facility.  The event focused on understanding the behavior of energized and arcing Corrugated Stainless Steel Tubing (CSST).  The event was presented by Dennis Shelp, Brent Fakuda, and Jennifer Poytner (Poynter Law).

Commercial Cooking Line Fires – AEI Flashover Friday’s Event

AEI Corporation hosted a Flashover Fridays, live burn event dealing with investigations and legal aspects of commercial cooking line fires. The overall objectives of the presentation were to provide information regarding ventilation control and fire protection for commercial cooking operations

AEI Hosts 5th Annual Charity Event

at Wings Over the Rockies Air & Space Museum, raising $6,350 for the Colorado Therapeutic Riding Center whose mission is to change the lives of people with disabilities by promoting their physical, psychological and social well being through equine assisted activites

Mr. Charles Brown

With 20 years of experience in the propane industry and 11 years in the natural gas industry, Mr. Brown is a recognized expert in code analysis, interpretation, implementation, compliance, standard of care, training, and safety. His extensive knowledge enhances AEI’s already deep bench of industry expertise, and we are pleased to welcome him to the team.

Scott Raszeja begins working at AEI

as Senior Project Engineer. Mr. Raszeja is an electrical forensic expert with over 30 years of experience as an Electrician and Electrical Engineer. He is an expert in market certifications for products, including product safety and electromagnetic compatibility certification.

This fun and informative event

Will provided guests with an overview of the guidelines for testing the integrity of natural propane fuel systems. Our presenter, Charlie Brown, discussed code requirements related to new construction, changes to existing gas systems and appliances, and changse to an occupancy.

Roxy Blea Joins AEI

Roxy Blea joined AEI as an Administrative Assistant in 2018, bringing with her 21 years of experience in office administration, customer support, and facilities and asset management. She now serves as AEI’s Office Administrator, ensuring the office runs smoothly and that clients are well supported and connected to the right resources within the organization.

Flashover Friday’s, “Gasoline Geysering”

Dennis Shelp led this presentation and training during a 2018 Flashover Fridays event, offering attendees an overview of potential safety hazards related to improper venting of gasoline fuel tanks in small engines, such as those used in riding mowers. His demonstration was filmed and aired on Denver's Channel7 News.

Scott Raszeja

earns Certified Interconnect Designer (CID+) Certification. The CID+ is IPC’s highest certification for Printed Circuit Board Design and is a valuable professional credential recognized throughout the electronics industry. Fewer than 1000 people worldwide have attained this level of certification.

AEI Hosts Flashover Friday’s, “The Internet of Things”

Live Burn Event. This event focused on Printed Circuit Boards, electronics, and fires resulting from different failure models. The Internet of Things, as it relates to these types of failure modes, was also discussed.

Brian Strandjord Joins AEI

Brian joins AEI as Senior Project Engineer in 2019. Mr. Strandjord is a licensed mechanical and electrical professional engineer with an extensive and diverse background. He investigates the origin and cause of fires and explosions, carbon monoxide incidents, and other mechanical and electrical matters.

Steve Foltz joins AEI

Mr. Foltz has an extensive background and experience as a forensic animator and architectural consultant. He holds a Master of Architecture from the University of Colorado at Denver and his LEED AP certification.

Jay Freeman Retires

In 2021, Jay Freeman, a founder of AEI, transitioned into retirement. As part of AEI’s ownership succession plan, former AEI President and Founder Jay Freeman will remain with AEI as a senior project engineer for historic projects pending litigation.  John Schumacher assumee the responsibilities and leadership role of President.

Donna Sprinkle Retires

AEI extends its heartfelt congratulations to Donna Sprinkle on her retirement after 11 dedicated years as Administrative Manager. Her invaluable contributions to our administrative operations and commitment to exceptional customer service will be deeply missed—though not as much as the camaraderie and sharp wit she brought to the team. We wish her every success in this new chapter.

Scott Sollars, Senior Project Engineer

Mr. Sollars holds a Bachelor of Mechanical Engineering degree from the University of Minnesota and is a licensed Professional Engineer in the State of Minnesota. His background includes expertise in mechanical systems, machine design analysis, safety and hazard evaluation, machine guarding, combustion mechanics, and fuel gas systems and components. He also has extensive experience investigating incidents involving fire, explosions, and carbon monoxide. AEI was proud to welcome Mr. Sollars to the team in 2021.

Taylor Wittwer, Administrative Manager

Following Donna’s retirement, AEI is pleased to welcome Taylor Wittwer as our new Administrative Manager. Taylor oversees the day-to-day administrative operations of AEI and provides essential support to both the firm and our clients. Her diligence and warm demeanor make her an invaluable and greatly appreciated addition to the team.

Zachary J. Jason becomes Partner/Principal Engineer

Ali Booth Joins AEI

Ali Booth joined AEI in 2022 as an Administrative Coordinator and has since advanced into the role of Technical Writer and Media Assistant. In this capacity, she plays a vital role in reviewing AEI’s technical reports and protocols, ensuring clients receive clear, accurate, and high-quality information. Ali is also responsible for developing and maintaining standard operating procedures. Additionally, she supports the creation of social media content that highlights AEI’s work and team.

Frank Croshal, Project Engineer with Emphasis in Oil & Gas Industry

Mr. Croshal is a graduate of the United States Military Academy at West Point, where he earned a Bachelor of Science in Engineering. He is a licensed Professional Engineer in both Oklahoma and Colorado. With over 40 years of experience in the upstream oil and gas sector, Mr. Croshal has held a range of roles—from Field Foreman to Facilities Manager—bringing deep expertise in production, operations, and facility management. AEI is proud to welcome his extensive knowledge and leadership to the team.

Matt Dare, Scientist, Joins AEI

Dr. Matt Dare brings a diverse background to AEI as a materials scientist, microscopy expert, materials characterization specialist, and surface chemistry analyst. He applies this expertise to perform root cause analysis of defects in a wide range of materials, including metals, plastics, glass, ceramics, thin films, and coatings. AEI is pleased to welcome Dr. Dare to our team.

SEM Added to AEI Laboratory

In 2022k AEI added a Scanning Electron Microscope (SEM) to its arsenal of scientific equipment. The SEM allows for detailed analysis of materials at a nano or micro-level, which is not possible with traditional optical microscopes. Use of the SEM can be scheduled along with the time of a trained, skilled technician in half or full business day increments.

Derek Nolen Joins AEI Team

AEI is excited to have Derek Nolen, Senior Project Engineer, join the team. Mr. Nolen is a mechanical forensic expert and brings more than 38 years of experience to the field as a Mechanical Engineer. His areas of expertise and trial experience include industrial and residential mechanical system and equipment failure analysis; explosion and fire analysis of LPG (propane and butane) and other flammable gas and liquid-related losses.

Adam Davis Joins AEI

In 2023, Mr. Davis joined as a Project Engineer. His diverse background as a mechanical engineer, safety engineer, and industrial hazard analyst add to AEI's areas of expertise. Adam uses these skills to perform risk assessments and root cause and hazard analyses related to the investigation of fires and mechanical matters such as mechanical failures and machinery design.

We are proud to announce that AEI Scientist

Matt Dare, has completed his Ph.D. in Systems Engineering. The degree focuses on a multi-disciplinary approach to managing and solving complex problems across a variety of industries. It involves learning about control systems, operations research, reliability and performance engineering, risk analysis, software engineering, and networking and security. Congratulations, Matt, on all of your hard work!

Tony Ulaszek retires from Denver Fire

and begins working at AEI full time. Tony has been with us since 2017, we are excited to announce that he is now a full-time "AEI'er!" Tony brings extensive expertise in fire and explosion investigations, with a deep knowledge of NFPA 921 and NFPA 1033 standards. He is highly skilled at managing complex investigations, often working alongside government and private sector agencies.

Charlie Brown Appointed to ANSI Z223 Committee

In 2024, Charlie Brown was appointed to the ANSI Z223 Committee, which collaborates with the NFPA 54 Committee to develop the National Fuel Gas Code. This code governs the installation and operation of gas piping systems and appliances using fuel gases, including natural gas and liquefied petroleum (LP) gas.

Jordan Beverly, BS, MSc

Jordan Beverly joins Corporation, in 2024. She is a skilled electrical engineer with a robust background in multiple electrical engineering disciplines. She holds a Master of Science in Electrical Engineering and brings valuable academic research and industry experience in semiconductor device fabrication, device physics analysis, and manufacturing processes. Her extensive skill set includes semiconductor device fabrication and analysis, programming, technical writing, and product testing. She is dedicated to excellence in the field and possesses the ability to communicate complex information effectively.

AEI Corporation’s President, John L

Schumacher, MChE, PE, CFI, CFPS, was selected to present his manuscript "Investigation of an Unintended Combustion Event During Transfilling of Compressed Oxygen Cylinders" at ASTM 16th International Symposium on Flammability and Sensitivity of Materials in Oxygen-Enriched Atmospheres in Prague, Czech Republic

Brian Strandjord Named Partner

In 2025, Brian Strandjord is named Partner. As a licensed mechanical and electrical professional engineer with an extensive and diverse background.  His experience ranges from thermal analysis of individual electronic components and assemblies to the design, implementation, and operation of automation systems for control of HVAC, mechanical, and lighting systems in large facilities.  His expertise in forensic engineering, coupled with his dedication to thorough and accurate investigations aligns perfectly with AEI’s mission of delivering reliable, high-quality forensic engineering services.

Paul Molina, Technician

Paul supports all of AEI’s laboratory facilities and oversees the proper collection, tracking, and storage of evidence for our clients. He also assists with laboratory sessions held at AEI and ensures that all lab and field equipment is properly maintained and calibrated. Paul holds a B.S. in Mechanical Engineering from the University of Houston. His professional background includes experience as a Senior Design Engineer at Pico Technologies, as well as serving as an Engineering and Science teacher at Cypress Creek High School and the Energy Institute High School in Texas.

Adam Davis Earns PE

AEI's Adam Davis can now boast his Colorado Professional Engineering license.  Congratulations to Adam Davis, PE, EIT, CFEI.

Adam Davis Earns CFEI

The National Association of Fire Investigation grants the Certified Fire & Explosion Investigator (CFEI) designation to professionals who are recognized as qualified in the field of fire and explosion investigations.