VERTEX has Experts that Talk the Talk and Walk the Walk.

Unlike others, VERTEX provides forensic consulting alongside traditional AEC services which allows for a 360 degree view of your project.

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Our forensics experts work alongside AEC specialists which enhances our skills and bolsters the credibility of our expert consultants.

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VERTEX delivers innovative solutions on complex projects globally.

Since 1995, VERTEX has completed over 90,000 projects.

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VERTEX believes in a Lifetime of Learning philosophy.

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VERTEX is looking for talented individuals to join a highly technical team of forensic consultants, design engineers, construction managers, and environmental scientists.

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Have a question or want to speak with a technical professional?

VERTEX is a multi-discipline firm with global coverage. Our international network of resources enables us to provide multi-national clients with the most qualified local professionals who understand the culture, language, and regulatory framework.

Call Us: 888.298.5162

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Call us at 888.298.5162.

Alexander JohnsenM.S., CIH

Senior Industrial Hygienist II, I.H.B.S.

Mr. Johnsen has over ten years of experience working on various construction and environmental remediation projects at residential, commercial, municipal, and government sites. With a broad clientele base ranging from individual homeowners to law firms, private contractors, and government agencies, Mr. Johnsen has worked extensively with a wide variety of environmental contaminants and cleanup procedures. Mr. Johnsen is an American Board of Industrial Hygiene Certified Industrial Hygienist and provides expertise in comprehensive industrial hygiene, regulatory compliance including OSHA and EPA program compliance, mold, asbestos, chemical exposure monitoring (e.g. formaldehyde, hexavalent chromium, cadmium, etc.) waterborne pathogens (e.g., Legionella, sewage, etc.), wildfire residue sampling assessments (soot/ash/char), COVID-19 consulting, illicit drug testing and remediation, and hazardous waste. As an expert, Mr. Johnsen has provided deposition testimony, written expert reports, and assisted colleagues with written defense reports.

Education & Certification

B.S. Biology, University of Colorado
M.S., Masters of Science, University of Denver

Asbestos Project Designer, State of CO
Air Monitoring Specialist, State of CO
Asbestos Building Inspector, State of CO
Methamphetamine Consultant, State of CO
Certified Industrial Hygienist (CIH)
Certified Mold Inspector, State of CO
USP 797 and Environmental Sampling, State of CO
OSHA 10-hour Construction Safety and Health
MSHA 40hr/Underground

AIHA Registered Specialist: Exposure Decision Analysis
OSHA Fall Protection and Retrieval Training
IAQA Course – Mold Health Effects, Sampling and Data Interpretation
e-RAILSAFE Railroad Safety Training
Certified X-Ray Fluorescence Lead-analyzer (XRF)

Expert Witness Services

Environmental, Air Quality

Environmental, Demolition & Abatement

Environmental, Environmental Compliance/Disclosure

Environmental, Environmental Safety

Environmental, Hazardous Waste

Forensics Technical, Safety