Occupational hygiene, also called industrial hygiene, is the anticipation, recognition, evaluation, control and prevention of workplace hazards. Hazards include biological agents (such as flu virus or mould), chemicals (such as asbestos or benzene), physical hazards (such as noise or vibration), and psychosocial factors (such as bullying or violence). Occupational hygiene surveys utilize standardized sampling and assessments techniques to evaluate exposure. A Registered Occupational Hygienist (ROH) is recognized as meeting standards for professional competence in occupational hygiene. ROH is the only Canadian-based occupational or industrial hygiene accreditation with membership in the International Occupational Hygiene Association (IOHA).