from competent training in the following areas of science and management: basic sciences (biology, chemistry, mathematics (statistics), physics); occupational diseases (illness, injury and health surveillance (biostatistics, epidemiology, toxicology)); health hazards (biological, chemical and physical hazards, ergonomics and human factors); working environments (mining, industrial, manufacturing, transport and storage, service industries and offices); programme management principles (professional and business ethics, work site and incident investigation methods, exposure guidelines, occupational exposure limits, jurisdictional based regulations, hazard identification, risk assessment and risk communication, data management, fire evacuation and other emergency responses); sampling, measurement and evaluation practices (instrumentation, sampling protocols, methods or techniques, analytical chemistry); hazard controls (elimination, substitution, engineering, administrative, ppe and air conditioning and extraction ventilation); environment (air pollution, hazardous waste). however, it is not rote knowledge that identifies a competent occupational hygienist. there is an "art" to applying the technical principles in a manner that provides a reasonable solution for workplace and environmental issues. in effect an experienced "mentor", who has experience in occupational hygiene is required to show a new occupational hygienist how to apply the learned scientific and management knowledge in the workplace and to the environment issue to satisfactorily resolve the problem. to be a professional occupational hygienist, experience in as wide a practice as possible is required to demonstrate knowledge in areas of occupational hygiene. this is difficult for "specialists" or those who practice in narrow subject areas. limiting experience to individual subject like asbestos remediation, confined spaces, indoor air quality, or lead abatement, or learning only through a textbook or “review course” can be a disadvantage when required to demonstrate competence in other areas of occupational hygiene. information presented in wikipedia can be considered to be only an outline of the requirements for professional occupational hygiene training. this is because the actual requirements in any country, state or region may vary due to educational resources available, industry demand or regulatory mandated requirements. during 2010, the occupational hygiene training association (ohta) through sponsorship provided by the ioha initiated a training scheme for those with an interest in or those requiring training in occupational hygiene. these training modules can be downloaded and used freely. the available subject modules (basic principles in occupational hygiene, health effects of hazardous substances, measurement of hazardous substances, thermal environment, noise, asbestos, control, ergonomics) are aimed at the ‘foundation’ and ‘intermediate’ levels in occupational hygiene. although the modules can be used freely without supervision, attendance at an accredited training course is encouraged. these training modules are available from oh learning.com academic programs offering industrial hygiene bachelor's or master's degrees in united states may apply to the accreditation board for engineering and technology (abet) to have their program accredited. as of october 1, 2006, 27 institutions have accredited their industrial hygiene programs. accreditation is not available for doctoral programs. in the u.s., the training of ih professionals is supported by national institute for occupational safety and health through their niosh education and research centers. australia in 2005, the australian institute of occupational hygiene (aioh) has accredited professional occupational hygienist through a certification scheme. occupational hygienists in australian certified through this scheme are entitled to use the phrase certified occupational hygienist (coh) as part of their qualifications. hong kong registered professional hygienist registration & examination board (rph r&eb) is set up by the council of the hong kong institute of occupational & environmental hygiene (hkioeh) with an aim to enhance the professional development of occupational hygienists and to provide a path for persons who reach professional maturity in the field of occupational hygiene to obtain qualification recognised by peer professionals. under hkioeh, rph r&eb operates the registration program of registered professional hygienist (rph) and qualifying examination in a standard meeting the practice as recognised by the national accreditation recognition (nar) committee of the international occupational hygiene association (ioha). united states practitioners who successfully meet specific education and work-experience requirements and pass a written examination administered by the american board of industrial hygiene (abih) are authorized to use the term certified industrial hygienist (cih) or certified associate industrial hygienist (caih). both of these terms have been codified into law in many states in the united states to identify minimum qualifications of individuals having oversight over certain activities that may affect employee and general public health. after the initial certification, the cih or caih maintains their certification by meeting on-going requirements for ethical behavior, education, and professional activities (e.g., active practice, technical committees, publishing, teaching). abih certification examinations are offered during a spring and fall testing window each year at more than 400 locations worldwide. the cih designation is the most well known and recognized industrial hygiene designation throughout the world. there are approximately 6800 cihs in the world making abih the largest industrial hygiene certification organization. the caih certification program was discontinued in 2006. those who were certified as a caih retain their certification through ongoing certification maintenance. people who are currently certified by the abih can be found in a public roster. the abih is a recognized certification board by the international occupational hygiene association (ioha). the cih certification has been accredited internationally by the international organization for standardization/international electrotechnical commission (iso/iec 17024) (see ansi). in the united states, the cih has been accredited by the council of engineering and scientific specialty boards . the association of professional industrial hygienists, inc. (apih) was established in 1994 to offer credentialing to industrial hygienists who meet the education and experience requirements found in tennessee code annotated, title 62, chapter 40. apih adopted the tennessee code as its basis for credentialing because it was the first legal definition in the united states of an industrial hygienist in terms of education and experience. the apih registration committee investigates and verifies, through electronic means or correspondence, both educational and experience accomplishments claimed by each applicant for registration. the committee determines the appropriate level of registration, registered industrial hygienist or registered professional industrial hygienist, and then authorizes the registration certificate to be issued. canada in canada, a practitioner who successfully completes a written test and an interview administered by the canadian registration board of occupational hygienists can be recognized as a registered occupational hygienist (roh) or registered occupational hygiene technician (roht). there is also designation to be recognized as a canadian registered safety professional (crsp). united kingdom the faculty of occupational hygiene, part of the british occupational hygiene society, represents the interests of professional occupational hygienists. membership of the faculty of occupational hygiene is confined to bohs members who hold a recognized professional qualification in occupational hygiene. there are three grades of faculty membership: licentiate (lfoh) holders will have obtained the bohs certificate of operational competence in occupational hygiene and have at least three years’ practical experience in the field. members (mfoh) are normally holders of the diploma of professional competence in occupational hygiene and have at least five years’ experience at a senior level. fellows (ffoh) are senior members of the profession who have made a distinct contribution to the advancement of occupational hygiene. all faculty members participate in a continuous professional development (cpd) scheme designed to maintain a high level of current awareness and knowledge in occupational hygiene. india the indian society of industrial hygiene was formed in 1981 at chennai, india. subsequently, its secretariat was shifted to kanpur. the society has registered about 400 members, about 90 of whom are life members. the society publishes a newsletter, "industrial hygiene link". the current address of the secretary of the society is shyam singh gautam, secretary, indian society of industrial hygiene, 11, shakti nagar, rama devi, kanpur 2008005 mobile number 8005187037.