On March 27, 1995, IOHA hosted an international workshop on certification in Blackpool, U.K. The goals of the workshop were to further the development and application of occupational hygiene and to enhance movement of occupational hygiene professionals across national borders.

To prepare for the workshop, IOHA published an inventory of existing certification/licensing schemes for occupational hygienists in Canada, Italy, Japan, The Netherlands, U.K. and USA (Certification of Occupational Hygienists, 1995). Since the workshop, several additional countries have implemented (Norway and Switzerland) or explored (Australia, Brazil, Denmark, Finland, Mexico, South Africa and Sweden) national certification programs.

The IOHA publication and the workshop discussions were used to develop IOHA's policy on International Certification. In that policy, the following objectives were set forth:

a. The development of appropriate national and international standards and practices to facilitate comparable levels of education and competence of professional occupational hygienists.

b. The avoidance of unnecessary restrictions from and within national certification schemes relating to the training and certification of hygienists and their ability to practice.

c. The sharing of technical information in relation to the training and certification of hygienists.

d. The development and wide application of principles of quality assurance to the education, training and competence of professional occupational hygienists.

It was also suggested that certifying boards explore the extent to which there is the ability to establish, through bilateral arrangements, a level of mutual recognition of training and competence.

In 1998, after reviewing progress since 1995, the Board of Directors recognized IOHA had not yet implemented an effort to facilitate attainment of the objectives described above. It was, however, recognized that our Association's leadership in bringing some degree of harmonization to national certification schemes was not only important but also crucial. The Board also noted the changing nature of employment, in particular the increasing provision of hygiene support across national boundaries, and also the poor level of provision in many parts of the world within developing or redeveloping economies. With additional national programs being considered and in some cases already implemented it seemed an appropriate time for IOHA to explore the interest and feasibility of holding a follow up workshop. Consequently, contact was made with the officers of the American Board of Industrial Hygiene (ABIH) and the British Institute of Occupational Hygienists (BIOH). Both organizations recognized the need for international collaboration on certification issues and expressed a willingness to join with IOHA in hosting an International Workshop to explore international cooperation in registration and certification. It was anticipated that other certification organizations, as well as national occupational hygiene associations, would share an interest in such a workshop and would participate in the undertaking.

To design the Plan of Action for the Workshop, the IOHA Executive asked Dr. Vernon Rose, Vice President, to develop a recommended plan and submit it to the Board of Directors for approval. In developing the Plan, Dr.Rose organized a working group consisting of Lynn O'Donnell, Executive Director of ABIH, Gun Nise of the Swedish Association of Occupational and Environmental Hygiene (IOHA Director), Martin Newell of the British Institute of Occupational Hygienists (IOHA Director) and Paul Oldershaw of the British Occupational Hygiene Society (IOHA President Elect). The proposed plan was also shared with Ugis Bickis of the Canadian Registration Board of Occupational Hygienists (IOHA Director). The Plan of Action was developed by the working group and approved by the IOHA Executive at their April 12, 1999 meeting.

On November 4-5, 1999, IOHA organized an international workshop to explore international cooperation in registration and certification. Participants included representatives from the existing national Certification Bodies (except for Italy), which included Canada, Norway, The Netherlands, Switzerland, USA and U.K., as well as representatives from Australia, Finland, Sweden and the WHO.

This 2nd Edition of the IOHA report "Certification of Occupational Hygienists", provides an update to the original Chapter 3 "National certification schemes", as well as a new Chapter 9 "1999 Workshop and recommendations". This latter chapter presents the aims, achievements and recommendations of the "1999 IOHA Workshop on Certification of Occupational Hygienists". In addition to collecting information on existing certification schemes IOHA member organizations were asked to submit copies of their Codes of Ethics. These Codes and the Model IOHA Code are presented in Appendix A of the 2nd Edition. Through publication of this 2nd Edition, the IOHA Board of Directors has accepted and endorsed the Workshop recommendations. IOHA has implemented the recommendations, specifically by establishing an IOHA Certification Committee, and started to identify and so designate national "IOHA Recognized Certification Boards.

In 2005 the committee was redesignated as the 'IOHA National Accreditation* Recognition Committee'. 

* The term “accreditation” is used here to encompass the diverse words used in different organizations (“certification”, “registration”, “faculty membership”) to describe the system/process for providing “credentials” designating professionalism in Occupational Hygiene.