OPIM stands for Other Potentially Infectious Materials. It’s a term created by OSHA (the Occupational Safety and Health Administration) as part of its Bloodborne Pathogens Standard to describe body fluids, tissues, and lab materials that can carry dangerous viruses like HIV, hepatitis B, and hepatitis C. If you’ve encountered this acronym in a workplace training or certification course, here’s what it covers and why it matters.
What Counts as OPIM
OSHA’s definition of OPIM falls into three categories. The first is a specific list of human body fluids: semen, vaginal secretions, cerebrospinal fluid (the fluid surrounding the brain and spinal cord), synovial fluid (in joints), pleural fluid (around the lungs), pericardial fluid (around the heart), peritoneal fluid (in the abdomen), and amniotic fluid (surrounding a fetus). Saliva also qualifies, but only during dental procedures, because contamination with blood during dental work is considered predictable.
The second category is any unfixed tissue or organ from a human body, living or dead, other than intact skin. “Unfixed” means the tissue hasn’t been treated with a chemical preservative.
The third category covers laboratory materials: HIV-containing cell or tissue cultures, organ cultures, culture medium or solutions containing HIV or hepatitis B, and blood, organs, or tissues from lab animals infected with either virus.
What’s Not Included
Several common body fluids are excluded from OPIM unless they contain visible blood. Sweat, tears, saliva (outside of dental procedures), urine, feces, and vomit do not qualify on their own. However, OSHA adds an important catch-all rule: when it’s difficult or impossible to tell what type of body fluid you’re dealing with, you treat all of it as potentially infectious.
Why OPIM Exists as a Category
Blood is the most well-known route of transmission for bloodborne pathogens, but it’s not the only one. HIV, hepatitis B, and hepatitis C, the three most common bloodborne pathogens, can also be present in the fluids and tissues listed above. OSHA created the OPIM category so that workplace safety rules would cover these additional transmission routes. Any worker who could reasonably come into contact with OPIM has what OSHA calls “occupational exposure” and is entitled to specific protections.
Who Needs to Know This
OPIM is most relevant to healthcare workers, dental professionals, lab technicians, first responders, janitorial staff in medical facilities, and anyone else whose job could bring them into contact with human body fluids or tissues. If your role involves potential exposure, your employer is required to have a written Exposure Control Plan that spells out how OPIM is handled at your workplace.
Required Protective Measures
OSHA requires employers to provide personal protective equipment at no cost to any worker with occupational exposure. The type of PPE depends on the task. Gloves are required whenever hand contact with OPIM, mucous membranes, or non-intact skin is reasonably anticipated. Masks combined with eye protection (goggles, glasses with side shields, or face shields) are required when splashes, sprays, or droplets of OPIM could reach your eyes, nose, or mouth. Gowns, lab coats, or similar outer garments are required during exposure situations. For tasks involving heavy contamination, such as autopsies or certain surgeries, surgical caps, shoe covers, or boots may also be necessary.
PPE is only considered adequate if it prevents OPIM from reaching your skin, eyes, mouth, mucous membranes, or clothing under normal use conditions for the full duration of the task.
Handling and Disposal Rules
OSHA’s Bloodborne Pathogens Standard sets specific work practice controls for OPIM. All procedures must be performed in a way that minimizes splashing, spraying, spattering, and droplet generation. Eating, drinking, smoking, applying lip balm or cosmetics, and handling contact lenses are all prohibited in work areas where exposure is reasonably likely. Food and drinks cannot be stored in refrigerators, freezers, or on surfaces where OPIM is present.
Containers used to store, transport, or dispose of materials contaminated with OPIM must carry a biohazard label with the standard biohazard symbol in a contrasting color against a fluorescent orange or orange-red background. A solid red container can be used as a substitute for the label. These labeling rules apply to regulated waste containers, storage containers, and shipping containers alike.
The Universal Precautions Principle
The foundation of OSHA’s approach to OPIM is a concept called universal precautions: treat all human blood and OPIM as if they are infectious, regardless of the source. You don’t wait for a confirmed diagnosis. You don’t assume a fluid is safe because the patient appears healthy. This principle exists because bloodborne pathogens can be present in someone who shows no symptoms, and because in real-world situations, identifying exactly which fluid you’re dealing with is often impossible.