Infection Control: Standard Precautions and Aseptic Technique — Limited X-Ray / Radiologic Technology

Objective. Students will correctly implement standard precautions—including hand hygiene, personal protective equipment selection, and equipment disinfection—and demonstrate sterile field setup appropriate for imaging procedures.

Why Infection Control Matters in Radiologic Technology

Radiologic technologists work with patients who may be immunocompromised, post-surgical, or carrying communicable diseases. The imaging suite—including the table, tube head, Bucky, and control panel—can harbor pathogens transferred from one patient to the next if proper precautions are skipped. Your role in preventing healthcare-associated infections (HAIs) is just as important as producing a diagnostic image. Failing to follow infection control protocols can harm patients, expose you to occupational illness, and put your state license at risk.

Standard Precautions

Standard precautions are the baseline level of infection prevention used with every patient, regardless of known diagnosis. They treat blood, all body fluids (except sweat), non-intact skin, and mucous membranes as potentially infectious. The CDC established standard precautions by combining earlier Universal Precautions with body substance isolation concepts.

Key elements include:

Hand hygiene — the single most effective way to prevent pathogen transmission.
Personal protective equipment (PPE) — selected based on the anticipated exposure (gloves, gown, mask, eye protection, face shield).
Respiratory hygiene/cough etiquette — offering masks and tissues to coughing patients.
Safe injection practices — never recap needles by hand; use sharps containers.
Equipment cleaning and disinfection — wipe down all patient-contact surfaces between every patient.

Hand Hygiene: The WHO Six-Step Technique

Alcohol-based hand rub (ABHR) is preferred when hands are not visibly soiled. Soap and water are required when hands are visibly dirty or after contact with Clostridioides difficile spores, because alcohol does not reliably kill spores.

The WHO six-step technique covers all anatomical zones:

1. Rub palm to palm.

2. Right palm over left dorsum; then left palm over right dorsum.

3. Palm to palm with fingers interlaced.

4. Backs of fingers against opposing palms (interlocked).

5. Rotational rubbing of the right thumb clasped in the left palm; then vice versa.

6. Rotational rubbing backward and forward with the fingers of the right hand in the left palm; then vice versa.

The entire process takes at least 20–30 seconds with soap and water (lather, rub all zones, rinse, dry) or 20–30 seconds with ABHR. The five moments for hand hygiene (WHO) are: before patient contact, before an aseptic task, after body fluid exposure, after patient contact, and after contact with the patient's environment.

Selecting and Using PPE

PPE protects both you and the patient. Select PPE based on the procedure's risk:

Gloves: Whenever contact with blood, body fluids, or non-intact skin is possible. Change gloves between patients; gloves are not a substitute for hand hygiene.
Gown: Protects clothing and skin during procedures likely to generate splashes or when the patient is on contact precautions.
Surgical mask: Protects mucous membranes from splashes; also used as source control for respiratory precautions.
Eye protection (goggles or face shield): Required when splashes to the eyes are possible—for example, when setting up a contrast injection tray.

Don sequence (CDC): gown → mask → eye protection → gloves.

Doff sequence (CDC): gloves → eye protection → gown → mask (hand hygiene between steps). Doffing order is designed so that the most contaminated item—gloves—comes off first, preventing self-contamination of the face and mucous membranes.

Levels of Disinfection and Sterilization

Not all surfaces require the same treatment:

Low-level disinfection: EPA-registered disinfectant wipes for non-critical items that contact only intact skin (imaging table surface, Bucky handle, control panel).
High-level disinfection: For semi-critical items that contact mucous membranes (some ultrasound probes used adjacent to imaging).
Sterilization: Eliminates all microorganisms including spores; required for critical items that enter sterile body cavities.

In the radiographic suite, wipe all patient-contact surfaces between patients using facility-approved disinfectant wipes and allow the manufacturer-specified contact (dwell) time before the surface is considered disinfected.

Aseptic Technique and Sterile Field Setup

When a procedure involves contrast media injection or other invasive elements, a sterile field must be established and maintained.

Principles of a sterile field:

1. Only sterile items enter the sterile field.

2. Sterile persons touch only sterile items; unsterile persons touch only unsterile items.

3. The sterile field is at or above waist level and within your direct vision.

4. The outer one-inch border of a sterile drape is considered contaminated.

5. A sterile field becomes contaminated if it is wet, if a non-sterile item passes over it, or if it is left unattended and out of sight.

6. Once you turn your back on the sterile field, it is considered contaminated.

Opening sterile packages: Peel back the outer wrap away from the field; let the contents drop onto the drape without reaching over it. Check package integrity and expiration date before opening.

Adding sterile liquids: Pour without splashing; the lip of the bottle is considered contaminated after first use.

Equipment Disinfection in the Imaging Suite

After each patient, wipe the imaging table, Bucky handle, cassette surfaces, and any positioning aids with an EPA-registered, facility-approved disinfectant. Allow dwell time. Portable X-ray units used in isolation rooms require full wipe-down before leaving the room. Flat-panel detectors should be wiped with products approved by the manufacturer to avoid surface damage.

Safety Points

Never reuse single-use items such as gloves or syringes.
Report any needlestick or splash exposure immediately per facility protocol.
If your sterile glove or sterile field is compromised, stop, re-glove or re-drape, and document the event.
Patients on transmission-based precautions (contact, droplet, airborne) require additional PPE beyond standard precautions; follow posted signage outside the room.

Key terms9

Standard precautionsCDC baseline infection prevention practices applied to every patient, treating blood, body fluids, non-intact skin, and mucous membranes as potentially infectious.

Hand hygieneCleaning hands with soap and water or alcohol-based hand rub using the WHO six-step technique to remove or kill pathogens and prevent transmission.

Personal protective equipment (PPE)Specialized clothing or equipment—including gloves, gown, mask, and eye protection—worn to protect healthcare workers and patients from infectious exposure.

Sterile fieldA designated area prepared with sterile draping and supplies in which all items and persons must be sterile; any breach renders the field contaminated.

Aseptic techniqueA set of practices designed to prevent the introduction of microorganisms into a sterile field or patient's body during invasive procedures.

Healthcare-associated infection (HAI)An infection a patient acquires while receiving treatment in a healthcare facility, not present or incubating at the time of admission.

Low-level disinfectionUse of an EPA-registered disinfectant to eliminate most vegetative bacteria and some viruses on non-critical surfaces that contact only intact skin.

Doff sequenceThe CDC-specified order for removing PPE—gloves first, then eye protection, then gown, then mask—designed to prevent self-contamination during removal.

Transmission-based precautionsAdditional infection control measures used when standard precautions are insufficient; categories include contact, droplet, and airborne precautions.

In class: Glo-Germ hand-hygiene demonstration: students wash hands using WHO six-step technique, then view UV-light results to identify missed areas; repeat until technique is correct. · Don and doff PPE (gloves, gown, mask, eye protection) following the CDC sequence while a partner uses a checklist; then reverse the process to demonstrate doff order for contamination prevention. · Set up a sterile field on an imaging table tray using sterile technique, add instruments without contaminating the field, and perform a simulated contrast-needle-tray preparation; instructor observes for breaks in technique.
Materials: Glo-Germ powder and UV flashlight, disposable gloves (multiple sizes), isolation gowns, surgical masks, eye shields, sterile drape kits, sterile gloves, simulated contrast tray supplies, CDC Hand Hygiene guideline poster, disinfectant wipes, imaging table
Check: Sterile-field setup checklist: zero critical breaks in sterile technique permitted for pass; hand hygiene must cover all six anatomical zones confirmed under UV light.

Practice check8

Answer each question, then check it. Nothing is recorded; this is your own practice.