About DOHSBase
Our team of occupational hygiene experts
Our Story
DOHSBase was founded in 1992 by members of the NVvA Working Group on Limit Values and Measurement Methods. What started as a specialist database for Dutch occupational hygienists has grown into a comprehensive platform with over 325,000 chemical substances, serving professionals across the Netherlands, France, and Europe.
In 2005, DOHSBase introduced the concept of kick-off values — conservative benchmarks for substances without formal occupational exposure limits. This methodology was officially recognised by the Dutch Labour Inspectorate in 2012 and remains a cornerstone of our approach to chemical safety.
Today, DOHSBase Online provides occupational hygienists, safety professionals, and regulatory experts with validated substance data, limit values, hazard classifications, and measurement methods — all in a single, hierarchy-structured platform updated twice yearly by our expert team.
Our Team
Theo Scheffers, MSc — Co-Founder & Senior Consultant
Theo is one of the original founders of DOHSBase and brings over 40 years of experience in occupational health and industrial hygiene. His career spans research (TNO), the biochemical industry (DSM), engineering (Royal Haskoning), and software development.
Theo co-developed the kick-off values methodology and is the creator of several widely used occupational hygiene tools including HYGINIST, BWStat, and IH-Aligner. His published research includes “On the Strength and Validity of Hazard Banding” in the Annals of Work Exposures and Health (2016), available on ResearchGate.
He is an Honorary Member of the NVvA (Dutch Association for Occupational Hygiene) and serves on the board of the European Platform for Occupational Hygiene (EPOH). He is a member of BOHS, AIHA, IOHA, and several other international professional bodies.
Geert Wieling — Co-Founder & Consultant
Geert is a registered occupational hygienist and co-founder of DOHSBase. He has been instrumental in building and maintaining the chemical substance database since its inception in 1992.
Together with Theo Scheffers, Geert co-authored the foundational kick-off values study published in the Journal for Applied Occupational Sciences (vol. 18, 2005). He is an active member of the NVvA, participating in the Working Group on Toxic Substances and the Working Group for Revision of Respiratory Protection Guidelines.
Geert is a regular presenter at NVvA events, sharing practical knowledge on hazard ranking methodologies and the application of DOHSBase in workplace chemical safety assessments.
Fenneke Linker — Consultant Industrial Hygiene & Toxicology
Fenneke brings over 30 years of experience in hazardous substances and risk evaluation to the DOHSBase team. She is a registered occupational hygienist and toxicologist, working through Arbo-Tox, Coaching & Consultancy and as a partner at PreventPartner.
Her expertise includes exposure assessments using in silico modelling and statistical evaluation, substance classification in health hazard bands, derivation of internal occupational exposure limits, and REACH dossier support. She has particular knowledge in the field of chemical substances and nanoparticles.
Fenneke is active in the Dutch Society of Toxicology and a speaker at international conferences including IOHA 2024.
Saskia Houben — Occupational Health & Safety Specialist
Saskia is an occupational health and safety professional with a PHOV postgraduate qualification in Occupational Safety and Health Management. She brings practical experience in chemical safety and hazardous substance management from her work in the Dutch occupational health sector.
Based in Echt, Limburg — the same region as DOHSBase headquarters — Saskia contributes her expertise in environmental modelling and workplace safety to the team. She is an active participant in NVvA symposia and professional development events.
Marcel Dumont, Owner & CTO
Marcel has been the owner of DOHSBase since 2025, bringing a combination of environmental chemistry expertise and IT leadership to the company. With a BSc in Environmental Chemistry, he bridges the gap between the scientific and technical aspects of the platform.
As CTO, Marcel oversees the development and infrastructure of DOHSBase Online, ensuring the platform remains reliable, secure, and accessible for occupational hygiene professionals across Europe.
Our Approach
Every data point in DOHSBase is reviewed and validated by our team of experienced occupational hygienists before it enters the database. We do not simply aggregate raw regulatory data — we interpret, contextualise, and structure it within the DOHSBase limit value hierarchy.
This expert validation process is what distinguishes DOHSBase from raw data feeds and generic chemical databases. When you consult DOHSBase, you can trust that the information has been assessed by professionals who understand the practical realities of occupational hygiene.
Professional Affiliations
Our team members are active in the following professional organisations:
- NVvA — Dutch Association for Occupational Hygiene (founding member, sponsor)
- BOHS — British Occupational Hygiene Society
- AIHA — American Industrial Hygiene Association
- IOHA — International Occupational Hygiene Association
- EPOH — European Platform for Occupational Hygiene
- NVvT — Dutch Society of Toxicology