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Standard &
Transmission-Based Precautions

Master the infection control practices that protect every patient and nurse — from hand hygiene to isolation rooms.

NCLEX-RN

Why Precautions Matter

Healthcare-associated infections (HAIs) cause harm and death every day. Nurses break the chain of infection by applying the right precautions at the right time.

The Chain of Infection

InfectiousAgent Reservoir(source) Portal ofExit Mode ofTransmission Portal ofEntry SusceptibleHost

Standard Precautions: Always

Applied to all patients regardless of diagnosis. Treat all blood, body fluids, secretions, excretions (except sweat), non-intact skin, and mucous membranes as potentially infectious.

1
Hand hygiene — the single most effective measure.
2
PPE based on anticipated exposure (gloves, gown, mask, eye protection).
3
Respiratory hygiene, safe injection practices, and proper disposal of sharps.

Transmission-Based: Three Types

Added on top of Standard Precautions when a specific pathogen is known or suspected. There are three categories:

Contact
Spread by touch or surfaces. Gown + gloves.
Droplet
Large droplets within ~6 ft. Surgical mask.
Airborne
Tiny particles that linger. N95 + negative pressure.

The Core Rule

Standard Precautions Foundation for every patient Transmission-Based Added when needed

Matching PPE to the Type

C
Contact: Gown and gloves on room entry. Dedicated equipment. Private room preferred.
D
Droplet: Surgical mask within 3–6 ft. Private room or cohort. Mask the patient during transport.
A
Airborne: N95 respirator (fit-tested). Negative-pressure (AIIN) room with door closed.

Droplet vs Airborne

The most-tested distinction. Particle size determines how far they travel and what mask you need.

Droplet
Particles > 5 microns. Fall within ~6 ft. Surgical mask. Examples: influenza, pertussis, meningitis.
Airborne
Particles < 5 microns. Stay suspended in air. N95 + negative pressure. Examples: TB, measles, varicella.

Memorize: Air = MTV

How to Apply Precautions

1
Always start with Standard Precautions for every patient.
2
Identify the organism and its route of transmission.
3
Add the matching tier — Contact, Droplet, and/or Airborne.
4
Don PPE before entry, doff before exit, and perform hand hygiene.

PPE Don & Doff Order

Donning (on)
1. Gown → 2. Mask/Respirator → 3. Goggles/Face shield → 4. Gloves
Doffing (off)
1. Gloves → 2. Goggles/Face shield → 3. Gown → 4. Mask (leave room, then remove mask)

Example 1: C. difficile

A patient has active Clostridioides difficile diarrhea. What precautions apply?

Example 2: Tuberculosis

A patient with suspected active pulmonary TB is admitted. What is the correct setup?

Example 3: Combined Precautions

A child is admitted with varicella (chickenpox), which spreads through air and through contact with vesicle fluid.

Common Mistakes

✕ Sanitizer for C. diff
Alcohol gel does not kill spores. Use soap and water.
✕ Surgical mask for TB
TB is airborne — it requires a fit-tested N95.
✕ Skipping Standard
Transmission-Based is added on top, never used alone.
✕ Wrong doff order
Remove gloves first; perform hand hygiene last.

Quick Reference Table

ContactDropletAirborne
PPEGown + glovesSurgical maskN95 respirator
RoomPrivate preferredPrivate / cohortNegative pressure
ExamplesMRSA, C. diffFlu, pertussisTB, measles

Question 1 of 5

A nurse cares for a patient with active pulmonary tuberculosis. Which PPE and room are required?

Question 2 of 5

Which hand hygiene method is required when caring for a patient with C. difficile?

Question 3 of 5

When doffing PPE, which item is removed first?

Question 4 of 5

Standard Precautions are used for:

Question 5 of 5

A patient with varicella (chickenpox) requires which combination of precautions?