3.2 Standard Precautions and Transmission-Based Precautions

Standard and Transmission-Based Precautions

CDC’s Standard Precautions apply to every patient regardless of diagnosis. They assume that blood, body fluids, nonintact skin, and mucous membranes can transmit infection and combine hand hygiene, PPE, respiratory hygiene, sharps safety, safe injection, environmental cleaning, and device reprocessing. OSHA separately creates enforceable worker-protection duties for occupational exposure.

Standard Precautions in Dental Care

Choose controls from the task and anticipated exposure:

• Hand hygiene: before and after patient contact, before an aseptic task, after body-fluid exposure risk, after touching contaminated surroundings, and immediately after glove removal. Use soap and water when visibly soiled; otherwise an alcohol-based hand rub is generally preferred for routine care.
• PPE: gloves for anticipated blood, saliva, mucous-membrane, nonintact-skin, or contaminated-item contact; protective clothing, mask or respirator, and eye/face protection selected for splash, spray, droplet, and inhalation hazards.
• Respiratory hygiene: signage, tissues, source control when indicated, hand-hygiene supplies, prompt separation of symptomatic people, and scheduling or referral decisions based on current guidance.
• Sharps and injections: engineering controls, safe recapping only when necessary, one needle and one syringe for one patient, and clean medication preparation.
• Patient-care items: clean before sterilization or disinfection and apply Spaulding classification plus the device IFU. Reusable handpieces and removable intraoral air/waterline devices are cleaned and heat sterilized between patients.
• Environment: barrier or clean and disinfect clinical-contact surfaces, and clean housekeeping surfaces by an appropriate low-dust method.

Standard Precautions are the floor, not the ceiling. A known or suspected infection may require additional Contact, Droplet, or Airborne Precautions.

Contact Precautions

Contact Precautions reduce spread by direct touch or contaminated equipment and surfaces. In a healthcare facility, they can require gown and gloves on room entry, dedicated equipment, enhanced environmental cleaning, and careful exit technique. The exact PPE and room workflow follow the pathogen-specific guidance and facility policy.

For suspected or confirmed C. difficile, soap-and-water handwashing is preferred after care and the environmental product must have the appropriate EPA claim and be used according to its label. Do not assume every quaternary ammonium product is sporicidal. Elective dental treatment is generally delayed when a patient has uncontrolled diarrhea or another illness that makes safe outpatient care impractical.

Droplet Precautions

Droplet precautions add source control, patient placement, and task-appropriate face/eye protection for infections primarily spread by respiratory droplets. Particle behavior is a continuum; a rigid “greater than 5 μm and only six feet” rule is outdated. Room airflow, procedure, source control, distance, and time all affect exposure.

In an outpatient dental office, screen before arrival, place a symptomatic patient away from others, have the patient wear source control when tolerated, and defer elective care until current pathogen-specific criteria are met. If urgent care proceeds, use the PPE and environmental controls indicated by the hazard assessment and public-health guidance. An ASTM mask level is chosen for fluid exposure; it is not automatically a respirator.

Airborne Precautions

Tuberculosis, measles, and varicella are classic airborne-precaution pathogens. Fine infectious particles can remain suspended and move with room air. Standard dental operatories are usually not airborne infection isolation rooms (AIIRs), so defer elective care for a patient with suspected or confirmed infectious airborne disease and arrange medical or public-health evaluation.

If emergency dental care cannot wait, refer to a facility with an AIIR meeting current ventilation criteria and a respiratory-protection program. Personnel use a fit-tested NIOSH-approved respirator or an appropriate PAPR. Existing and newly constructed AIIRs can have different engineering criteria; follow the applicable building and infection-control standard rather than assigning every dental room one ACH value. Exhaust or HEPA-filtered recirculation, pressure monitoring, and room clearance are managed by the receiving facility.

A surgical mask placed on the patient is source control during transport; it does not convert an ordinary operatory into an AIIR.

Patient Triage and Scheduling

A front-desk and chairside triage process asks about fever, cough, rash, vomiting or diarrhea, known airborne infection, recent exposure, and public-health isolation instructions. Staff should know who makes the clinical decision and how to arrange referral.

• Suspected infectious TB: provide source control when tolerated, separate the patient, defer elective care, and refer for evaluation. Return to routine dental care follows the treating clinician or public-health determination of noninfectiousness—not a dental-office rule requiring a fixed number of sputum smears.
• Acute respiratory illness: postpone elective care when symptoms or current public-health guidance indicate transmissibility or when the patient cannot tolerate source control. Use current healthcare criteria rather than a universal 24- or 48-hour rule.
• Varicella, measles, or disseminated zoster: avoid routine outpatient exposure and coordinate airborne-precaution care.
• Active oral or perioral lesions: evaluate whether treatment will manipulate the lesion, generate contamination, or expose a high-risk patient or worker; defer or modify care using clinical judgment rather than one rule for every cold sore.

Selecting the Added Precaution

Ask four questions:

1. What route or routes transmit the suspected pathogen?
2. Is the planned procedure likely to generate splash, spray, fine particles, or direct contact?
3. Does the room provide the needed environmental control?
4. Can care be safely deferred or referred?

Do not use a gown or N95 as a substitute for a missing isolation room, and do not delay emergency referral while trying to retrofit a general operatory. The exam-safe hierarchy is: Standard Precautions for all; add route-specific controls; defer or refer when the required environment is unavailable.