The 5 Principles of Industrial Hygiene


July 28, 2021

Occupational hygienist monitoring chemical exposure.

Anticipation, Recognition, Evaluation, Control and Confirm

Industrial hygiene, also known as occupational hygiene, is the science and art of protecting and enhancing the health and well-being of workers and citizens of the community. The field of industrial hygiene tackles a wide range of job-related hazards including:

  • Chemical

  • Physical

  • Biological

  • Psychological

  • Ergonomic stressors

Occupational hygienists apply the 5 basic principles of industrial hygiene to prevent injury and illness. These are:   

  1. Anticipation

  2. Recognition

  3. Evaluation

  4. Control

  5. Confirm

1. Anticipation of Health Hazards

Anticipation of health hazards is the first principle of industrial hygiene and is essential to keeping workplaces safe. This typically requires a survey of the workplace design, operations, processes, work tasks, materials and worker population. A current inventory of chemicals and their Safety Data Sheets will quickly identify all the chemical hazards in the workplace. The hazardous properties of each chemical onsite can help to prioritize which hazards need to be investigated.

2. Recognition of Health Hazards

Recognition of health hazards is the second principle of industrial hygiene. It is important to recognize and understand the potential hazards of the work environment, internal processes, and job tasks, including chemical and physical hazards at a workplace. For example, do some employees have greater exposure to occupational hazards because they work in an area with poor ventilation, or their work tasks generate a lot of dust, or their work shift or task is longer.  This also includes individual work tasks and how they affect adjacent work activities that could create exposure to hazards for other workers in the facility, also called simultaneous operations.  

Another step of recognizing health hazards is to know if there are occupational exposure limits or restrictions for the hazardous products identified in your chemical inventory.

3. Evaluation of Exposure

Evaluation of exposure is the third principle in industrial hygiene. Engineering, work practice, and administrative controls are the primary means of reducing employee exposure to occupational hazards. After anticipating and recognizing your health hazards, it’s time to evaluate the risk of exposure through an Occupational Exposure assessment.

Traditionally evaluation means workplace monitoring. Due to the complexity of the work environment and the measuring instruments, monitoring should only be done by a qualified professional like an industrial or occupational hygienist.

Industrial Hygiene Monitoring

Industrial hygiene monitoring captures the exposure level of a certain population of workers during their work activities at a certain time. This measurement can be conducted on those with the highest potential exposure, or a representative exposure, measurements can also refer to a similar exposure group (SEG), workers who perform the same tasks at the same frequency, with similar materials.  

Industrial hygiene monitoring measures a specific physical, biological or chemical agent where the exposure occurs. Monitoring also needs to consider variations in exposure during different work shifts or facility maintenance activities like turn arounds. Monitoring will have a defined purpose or question it is trying to answer; generally, it is trying to determine if exposures are safely below or over the occupational exposure limits (OEL) for the hazardous product.   

Qualitative and quantitative analysis of data from monitoring is used to determine if exposure results are acceptable, unacceptable, or uncertain.  Coming to this conclusion requires a knowledge of the occupational exposure limit in the jurisdiction in which you are operating. OELs for long-term and short-term exposure to a hazardous substance vary by province, state, and country.  

Not all substances in commerce have OELs developed for them.

4. Control Over Worker Exposure

Controlling worker exposures is the next principle of industrial hygiene.  When hazardous exposure is determined to be unacceptable, controls need to be implemented to protect workers. The hierarchy of controls should be used to guide decisions on a multifaceted approach to exposure control. Although people instinctively think of Personal Protective Equipment or PPE first, it should be the last control applied once elimination, substitution, engineering controls and administrative practices are considered.

5. Confirmation of Control Measures

Confirm is the last principle of industrial hygiene. This step highlights the importance of assessing the performance of hazard control measures and subsequently worker exposures. Investigating issues (including potential) and applying corrective actions is also part of confirming that your industrial hygiene program is effective. Maintaining data and reports is also key to the ability to track and trend the success of your industrial hygiene program to prevent injury, illness, or negative affects to the well-being of workers.

Develop an Industrial Hygiene Program with CHAMP

The principles of industrial or occupational hygiene are dynamic and require continual evaluation and reassessment as new hazards are introduced to the workplace and facilities change. Following these principles will protect a workplace’s most valuable asset: its people. Chemscape’s Chemical Hazard Assessment Management Program, also known as CHAMP, has the tools to help you identify and effectively management the chemical hazards in your workplace.