SAIOH has its origins in the Occupational Hygiene Association of South Africa (OHASA) which was established in 1983 to promote an awareness of Occupational Hygiene. The Institute of Occupational Hygienists of South Africa (IOHSA) was established in 1993 to register Occupational Hygienists who meet appropriate standards of education and practical experience. These two bodies merged in 2000 to form the present day SAIOH.
SAIOH has approximately 900 members and an annual budget of about a million rand which is applied to branch and head office incidentals. SAIOH is dependent on sponsorship and membership fees to sustain itself and provide a service to members. These service include, but not limited to