Flavorings Related Lung Disease: Workplace Interventions

Workplace Interventions

If air levels of alpha-diketones (e.g., diacetyl or 2,3-pentanedione), carbon monoxide, or carbon dioxide in workplace air exceed relevant occupational exposure limits, interventions should be put in place to reduce the air levels. Repeated air sampling can help evaluate whether the interventions are working as designed.

The hierarchy of controls is an approach that groups actions by their likely effectiveness in removing or reducing hazards.

hierarchy of controls image


Examples of workplace interventions based on the hierarchy of controls include the following:

Engineering Controls

Engineering controls can reduce employees’ exposures by removing the hazard from the process or by placing a barrier between the hazard and the employee. Engineering controls protect employees effectively without placing primary responsibility of implementation on the employee. Some examples of engineering controls are:

  • Local exhaust ventilation: Use local exhaust ventilation to capture and remove diacetyl and 2,3-pentanedione where they are produced or released such as at roasters, grinders, hoppers of off-gassing roasted coffee, packaging areas, and flavoring areas.
  • Dilution ventilation: Assess the general ventilation system to determine if more outdoor air needs to be introduced to the facility. Increasing fresh air exchanges reduces contaminant concentrations by diluting and exhausting generated contaminants. Any ventilation changes should be done in consultation with a qualified ventilation engineer to ensure proper airflow patterns and system balancing.
  • Enclose and automate processes: Minimize production tasks that require employees to place their heads inside the roasted bean bins or near roasted coffee. Do not blend roasted beans by hand. Instead, use an automatic mechanism that minimizes employee contact with roasted beans during blending. Cover bins of roasted beans to reduce the overall emission of alpha-diketones and other chemicals (e.g., carbon monoxide, carbon dioxide) into the workplace and to lower worker exposure.

Administrative Controls

Administrative controls are employer-dictated work practices and policies to reduce or prevent exposures to workplace hazards. The effectiveness of administrative changes in work practices for controlling workplace hazards is dependent on employer commitment and employee acceptance.  Some examples of administrative controls are:

  • Ensure workers understand the potential hazards (e.g., diacetyl, 2,3-pentanedione, carbon monoxide, carbon doxide, green and roasted coffee dust) in the workplace and how to protect themselves. OSHA’s Hazard Communication Standard, also known as the “Right to Know Law” [29 CFR 1910.1200] requires that employees are informed and trained of potential work hazards and associated safe practices, procedures, and protective measures.
  • Eliminate the use of compressed air and dry sweeping as much as possible for cleaning. Instead, use a vacuum system with a high-efficiency particle air filter and wet methods whenever possible.
  • Encourage employees to report new, persistent, or worsening respiratory symptoms (such as cough, shortness of breath on exertion, and/or wheezing) to their personal healthcare providers and to a designated individual at their workplace. The occurrence of new or ongoing respiratory symptoms in the workforce should prompt consideration of work-related lung disease, medical referral, and re-evaluation of the potential for exposure to respiratory hazards.

Personal Protective Equipment

The effectiveness of personal protective equipment (PPE) in the form of respiratory protection in controlling respiratory exposures depends on avoiding breakdowns in implementation that can result in insufficient protection. Proper use of respiratory protection (respirators) requires a comprehensive respiratory protection program and a high level of employee and management involvement and commitment to assure that the right type of respirator is chosen for each hazard, respirators fit users and are maintained in good working order, and respirators are worn when they are needed. Supporting programs such as training, change-out schedules, and medical assessment may be necessary. Respirators should not be the sole method for controlling hazardous inhalation exposures. Rather, respirators should be used until effective engineering and administrative controls are in place.

  • N95 respirators are not protective against alpha-diketones (e.g., diacetyl, 2,3-pentanedione). In cases of dual exposure to dust and alpha-diketones (i.e., diacetyl or 2,3-pentanedione), NIOSH-certified organic vapor cartridges for the alpha-diketones and particulate cartridges/filters for the dust would be warranted.

Medical Surveillance

The purpose of a medical monitoring program is to help assure the health of employees who have workplace exposures (e.g., diacetyl, 2,3-pentanedione, coffee dust) known to pose risk for potentially serious health conditions such as asthma or obliterative bronchiolitis.

  • If workplace air levels of diacetyl or 2,3-pentanedione in coffee roasting and packing facilities are above NIOSH exposure limits, we recommend a medical surveillance program, including a health questionnaire and spirometry, be initiated to screen for respiratory symptoms or respiratory abnormalities in employees.
  • Sometimes workers with obliterative bronchiolitis are initially misdiagnosed with asthma, chronic bronchitis, emphysema, or pneumonia; or their symptoms are attributed to smoking. It is important to consider the possibility of flavoring chemical-related lung disease in workers who have been exposed to diacetyl or 2,3-pentanedione and have respiratory symptoms. In cases of flavoring chemical-related lung disease, respiratory symptoms do not typically improve when the worker goes home at the end of the workday, on weekends, or on vacations.

Smoking Cessation Program

  • Prevention of smoking-related lung disease is important. Prevention is especially important in a workplace with risk of occupational lung disease, and makes the detection of work-related adverse effects easier.
  • The Centers for Disease Control and Prevention offers tools and resources for setting up a smoking cessation program [CDC 2017].
Ongoing Research
  • NIOSH is aggregating health and air sampling data collected in NIOSH health hazard evaluations at multiple coffee facilities to improve our understanding of respiratory health risks in this industry.
  • NIOSH is also evaluating the efficacy of engineering controls in reducing exposures to diacetyl and 2,3-pentandione during coffee processing activities. Lessons learned during these evaluations will be used to develop effective engineering control strategies that can be utilized in any coffee processing facility to reduce diacetyl and 2,3-pentanedione exposures.


Page last reviewed: June 28, 2018