Hierarchy of Controls
Total Worker Health Hierarchy of Controls Model
According to NIOSH, this must perform the following five control steps in order, or simultaneously: • Eliminate workplace conditions that cause or contribute to worker illness and injury or otherwise negatively impact well-being; • Replace unsafe, unhealthy working conditions or practices with safer, health-enhancing policies, programs, and management practices that improve the culture of safety and health in the workplace; • Redesign the work environment to remove impediments to well-being, enhance employer-sponsored benefits, and provide flexible work schedules; • Provide safety and health education and resources to enhance individual knowledge for all workers; AND, • Encourage personal change that will assist workers with individual risks and challenges and provide support for healthier choices.
Total Worker Health
An approach that prioritizes a hazard-free and healthy work environment through the application of a hazard control and prevention approach, consistent with the traditional hierarchy of controls model.
Chemical Protective Clothing
CPC
Level D PPE
Comprised of normal, everyday work clothes with no respiratory protection and minimal skin protection, although optional PPE can be added.
Administrative Controls
Controls that involve changes in work procedures such as written safety policies, rules, supervision, schedules, and training with the goal of reducing the duration, frequency, and severity of exposure to hazardous chemicals or situations. Also referred to as "work practice controls."
Written PPE Program
PPE selection criteria should be covered here. It is important to involve employees in hazard assessments and PPE selection, because they have advanced knowledge of the tasks and will be wearing the selected equipment. Involving employees in the PPE selection process will help them understand where the assessments come from, how they were performed, and should foster buy-in to new PPE procedures.
Engineering Controls
Protects workers by removing or controlling hazardous conditions, or by placing a barrier between the worker and the hazard.
Substitution
Replacing the hazard, is the second most effective method and is the process of substituting chemicals or substances that do not cause harmful effects.
Safety Data Sheets
SDS
Personal Protective Equipment
Shields or isolates individuals from the chemical, physical and biological hazards that may be encountered. However, employers must institute all feasible elimination, substitution, engineering and administrative controls to reduce hazards before using this method to protect workers. This should be the last choice for hazard control.
Level B PPE
Should be selected when the highest level of respiratory protection is needed and some degree of skin protection is required. This is the minimum recommendation for initial site entry where contamination is unknown.
Level C PPE
Should be selected when the types and concentrations of airborne contaminants are known, the criteria for using air-purifying respirators are met, and direct contact does not pose a skin hazard.
Elimination
The highest level of control in this model, which means that the hazard is physically removed from the work area.
Level A PPE
The highest level of protection. This is required when: • Conditions at a site are unknown; • Hazardous substances have been identified that require a high level of protection for skin, eyes, and the respiratory system; • There is potential for splash, immersion, or exposure to vapors, particulates, or gases that are harmful to the skin or may be absorbed through the skin; • Confined-space entry may be involved and the need for Level A cannot be ruled out; AND, • The skin absorption hazard may likely result in immediate death or serious illness or injury, or impair the ability to escape.
Permeation
The process by which a chemical dissolves in, or moves through, a material on a molecular basis.
Job Hazard Analysis
The steps necessary to assess potential hazards must be identified in every employee's workspace.
Degradation
This involves physical changes in a material as the result of a chemical exposure, use, or ambient conditions, such as sunlight.
Penetration
This is the movement of chemicals through zippers, seams, or imperfections in a protective clothing material.