Accreditation Criteria

Designation comparison

Core accreditation requirements.

Criteria	RAIH (SG)	RIH (SG)
Qualification	Basic degree in occupational hygiene, engineering, science, or a related field.	Basic degree in occupational hygiene, engineering, science, or a related field.
OH/IH coursework	Coursework expectations are reviewed according to the candidate's qualification pathway and submitted evidence.	Minimum of 150 hours of occupational hygiene or industrial hygiene coursework.
Practical experience	Candidates with an OH/IH degree require one year of practical experience. Candidates with a non-OH/IH degree or Specialist Diploma in Occupational Hygiene require two years of practical experience.	At least four years of practical experience in occupational hygiene or industrial hygiene.
Professional competency assessment	Professional competency is assessed through an interview.	Professional competency is assessed through an interview. Some candidates may be required to complete a written examination before the interview stage.
Assessment route	The RIH Board reviews the submitted application and determines the appropriate assessment pathway.	Candidates with an OH/IH degree may proceed directly to interview. Candidates with SDOH or without a recognised OH/IH degree must first pass a written examination before the interview stage.
Professional conduct	Applicants are expected to uphold the Code of Ethics and maintain responsible professional practice.	Applicants are expected to uphold the Code of Ethics, maintain professional competency, and support high industrial hygiene standards through continuing practice and learning.

Criteria by designation

Two levels of recognition for industrial hygiene practice.

Associate designation

RAIH (SG) application

RAIH (SG) registration is intended for practitioners who meet the basic qualification requirements and can demonstrate relevant practical experience in occupational hygiene, industrial hygiene, engineering, science, or a related field.

Basic degree in occupational hygiene, engineering, science, or a related field.
One year of practical experience for candidates with an OH/IH degree.
Two years of practical experience for candidates with a non-OH/IH degree or SDOH.
Professional competency assessed through an interview.

Registered designation

RIH (SG) application

RIH (SG) registration recognises practitioners with the required academic preparation, OH/IH coursework, and substantial practical experience in professional industrial hygiene practice.

Basic degree in occupational hygiene, engineering, science, or a related field.
Minimum of 150 hours of occupational hygiene or industrial hygiene coursework.
At least four years of practical experience in occupational hygiene or industrial hygiene.
Professional competency assessed through an interview, with written examination where required.

Assessment route

The RIH Board determines the appropriate assessment path.

Candidates submit their application to the OEHS Secretariat with the required supporting documents. The RIH Board reviews each application against the relevant qualification and experience pathway before confirming whether the candidate proceeds directly to interview or must first complete a written examination.

1

Submit documents

Submit the completed application, IH coursework form, official university transcript, and required supporting evidence to the OEHS Secretariat.

2

Board review

The RIH Board reviews the applicant's qualifications and determines the relevant assessment route.

3

Assessment

Eligible candidates proceed to interview. Candidates with SDOH or without a recognised OH/IH degree must first pass a written examination before the interview stage.

Assessment basis

A balanced review of qualification, practice, and professional conduct.

Education and coursework Candidates should provide evidence of relevant academic learning, specialist occupational hygiene coursework, or recognised equivalent preparation.
Practical experience Experience should demonstrate workplace application of industrial hygiene principles, monitoring, risk assessment, interpretation, and exposure control recommendations.
Technical proficiency Assessment may cover chemical, physical, biological, ergonomic, and environmental health stressors relevant to occupational hygiene practice.
Ethics and professional standing Candidates must understand and uphold ethical duties, confidentiality, competence boundaries, and responsible communication.

Core IH sequence

The criteria support recognised industrial hygiene practice.

The RIH (SG) Scheme supports the professional practice sequence used in occupational and industrial hygiene: anticipation, recognition, evaluation, and control. Recognition means identifying existing hazards in the workplace that may affect worker health.

01

Anticipation

Foreseeing potential health hazards before exposure problems arise.

02

Recognition

Identifying existing hazards in the workplace that may affect worker health.

03

Evaluation

Using suitable monitoring, sampling, and interpretation methods to understand exposure.

04

Control

Recommending practical measures that reduce exposure and safeguard worker health.

Criteria for RAIH (SG) and RIH (SG) accreditation.