Standard and transmission-based precautions
Standard precautions are infection control practices applied to every patient, while transmission-based precautions add contact, droplet, or airborne measures for patients known or suspected to carry specific infectious organisms.
Standard and transmission-based precautions are the two tiers of infection control used throughout healthcare. Standard precautions apply to the care of every patient, every time, regardless of diagnosis, because any patient's blood, body fluids, non-intact skin, and mucous membranes may contain infectious agents. Core elements include hand hygiene, gloves and other personal protective equipment (PPE) when exposure is possible, respiratory hygiene, safe injection practices, and proper handling of contaminated equipment and linens.
Transmission-based precautions form the second tier, added on top of standard precautions when a patient is known or suspected to be infected with an organism that spreads by a particular route. There are three categories. Contact precautions (gown and gloves, dedicated equipment) address organisms spread by touch, such as C. difficile and MRSA. Droplet precautions (surgical mask within close range) address pathogens carried in large respiratory droplets, such as influenza and pertussis. Airborne precautions (fitted N95 respirator and a negative-pressure isolation room) address pathogens that remain suspended in air, classically tuberculosis, measles, and varicella.
The two-tier system matters because it balances universal safety with targeted control: standard precautions protect against unrecognized infections, while transmission-based precautions interrupt the specific route a known organism uses. Choosing the correct category — and the correct PPE, donned and doffed in the correct order — is a daily clinical decision for nurses, medical assistants, and therapists.
The NCLEX, CCMA, and NPTE-PT exams all test this material. Expect questions matching diseases to their precaution category, selecting appropriate PPE, and applying isolation requirements such as negative-pressure rooms for airborne pathogens.
Key takeaways
- Standard precautions apply to all patients at all times and center on hand hygiene and appropriate PPE.
- Transmission-based precautions are added for known or suspected infections and come in contact, droplet, and airborne categories.
- Contact precautions require gown and gloves; droplet precautions require a surgical mask; airborne precautions require an N95 respirator and negative-pressure room.
- Classic airborne pathogens are tuberculosis, measles, and varicella.
- The NCLEX, CCMA, and NPTE exams test matching diseases to precaution categories and selecting correct PPE.