Patrick Usereau


Geologist / Petrographer

Patrick Usereau is the owner and President of Sedexlab inc., materials testing laboratory and consulting firm, which he founded in 1999.  As a registered Quebec Geologist, he has 20 years of experience in the field of expansive reactions related to iron-sulfide-containing aggregates, overseeing over 20,000 building assessments related to pyrite and pyrrhotite-bearing aggregate used in the residential and commercial construction industry.  Over the past years, Patrick has overseen petrographic examinations on more than 1000 concrete cores sampled from building foundations at risk with concrete deterioration related to pyrrhotite-bearing coarse aggregate. Moreover, his extensive background has enabled him to build a highly skilled and effective team of petrographers and technicians.

As President, Patrick is responsible for the leadership of the company, marketing efforts and business strategies. He works closely with the Project Managers on contracting, budgets, client satisfaction and quality control. Being the leader of a small business Patrick finds himself relying on his varied skills to complete a wide range of tasks.  He succeeds in facilitating a team environment that empowers his employees resulting in the successful operation of the company.

Francois Hamel

Operations Manager

Geologist / Petrographer

Francois is a Licensed Professional Geologist, member of the Order of Geologists of Quebec (OGQ).  He serves as Sedexlab’s Operations Manager since 2009.  His expertise lies mainly in the fields of soils, aggregate and concrete.

As the head of operations, Francois has managed quality assurance and quality control on a diverse array of materials testing projects from residential pyrrhotite assessments to industrial asbestos surveys. Francois has overseen thousands of pyrite building assessments and was a key asset in developing our pyrrhotite assessment division back in 2013. He has also supervised hundreds of asbestos surveys and environmental site assessments.

Francois has demonstrated strong leadership in mentoring, coaching and training technical staff and in the ability to multi-task in a fast-paced environment

Maxime Rousseau

Project Manager

Geologist / Petrographer

Max is a Licensed Professional Geologist, member of the Order of Geologists of Quebec (OGQ).  He is highly skilled in the geotechnical, materials testing, and inspection fields.  He serves as project manager and specializes in pyrite and pyrrhotite assessments, geotechnical studies as well as in asbestos surveys.  He joined Sedexlab Materials Testing and Consultancy in 2012.

Max was also a key component in implementing our pyrrhotite testing services following his participation in an important Hydro-Quebec funded study completed in 2013 and dealing with concrete deterioration due to the oxidation of iron sulfides.

Max provides deep insights during the analysis of concrete core samples identifying potentially reactive aggregates and quantifying iron-sulfide minerals in coarse aggregates.

Pascal Fortin

Project Manager

Geologist / Petrographer

Pascal is a Licensed Professional Geologist, member of the Order of Geologists of Quebec (OGQ).  He joined Sedexlab Materials Testing and Consultancy in 2007.  Pascal has performed thousands of microscopic examinations on aggregate, concrete and asbestos-containing materials.

He is our go-to guy when it comes to optical mineralogy and microscopy and a key asset for pyrrhotite and other iron-sulfide minerals identification and quantification.

Pascal serves as project manager and specializes in pyrite and pyrrhotite assessments as well as in asbestos surveys.

Ryan White

Chief Field Technician

Ryan joined Sedexlab in 2005. He has been a Field Manager since 2008 and is certified as an asbestos inspector by ATC Group Services.  His expertise lies mainly in the areas of inspection and sampling techniques for the purpose of material testing and laboratory analysis.

Ryan has performed and supervised thousands of sampling campaigns for surveys related to pyrite, pyrrhotite, vermiculite and other materials containing asbestos.   He is our reference in terms of supervision and training of technical field staff.