Scene Safety, Standard Precautions and PPE Selection

Scene Size-Up and the Safety Hierarchy

Scene size-up is the foundational phase of every emergency call. It does not begin when you step out of the ambulance; rather, scene size-up begins upon receipt of dispatch information and continues throughout the incident. From the moment the dispatch tones drop, the emergency medical technician must process caller information, location details, and environmental reports to anticipate potential hazards. Because scene safety is dynamic and must be continually reassessed during patient care, an emergency medical technician cannot assume a scene remains secure simply because it was calm on arrival.

On every emergency call, the primary priority of the emergency medical technician is personal safety. Prioritize your safety and your partner’s safety, then protect patients and bystanders from hazards; do not rely on a rigid ranking between patients and bystanders. While your natural instinct as a caregiver may be to run forward to help a critically injured person, becoming injured yourself eliminates your ability to help and creates an additional patient for incoming crews to manage.

During this initial assessment, the emergency medical technician should identify the mechanism of injury for trauma calls or the nature of illness for medical complaints. Identifying these factors assists in determining the severity of the situation. At the same time, determining the total number of patients early allows the emergency medical technician to request appropriate additional resources. When complex needs are discovered, additional resources such as advanced life support, fire, or heavy rescue should be requested as soon as the need is recognized.

Environmental, Physical, and Roadway Hazards

Emergency scenes often contain serious physical and environmental hazards that require immediate recognition and specialized resources. Downed power lines present an invisible and lethal threat. Downed power lines must always be treated as energized until utility personnel confirm they are de-energized. Emergency medical technicians must stay well clear of downed electrical wires, keep others away, and request fire and utility personnel to mitigate the danger before approaching any patients.

Special rescue situations require strict operational discipline. An emergency medical technician must not enter a trench, confined space, or burning structure. These environments present structural collapse, oxygen deficiency, and thermal threats that basic medical protective gear cannot withstand. Instead, stage in a safe location and request trained rescue personnel who possess the specialized equipment and training required to operate in these environments.

Roadway incidents present another continuous physical threat from moving traffic. When working in or near traffic, EMTs should wear compliant high-visibility apparel; when fire or heat makes a safety vest inappropriate, wear the protective apparel required by incident command and local protocol. Additionally, emergency vehicles should be positioned to shield the scene and providers from oncoming traffic. Turnout gear provides valuable physical protection during fire and extrication scenes, but it is designed specifically for physical protection and extrication rather than as standard medical protective wear.

Enclosed spaces require vigilance regarding airborne toxins. Emergency medical technicians should remain alert for environmental toxins such as carbon monoxide in enclosed spaces. A critical indicator of an environmental hazard is the presence of multiple symptomatic patients in an enclosed space, which strongly suggests a hazardous materials or toxic gas incident. In any hazardous materials release, emergency medical technicians should remain outside the hazardous materials hot zone and await appropriately trained and equipped hazmat personnel. Stage the ambulance uphill, upwind, and a safe distance from the release, following incident command and local protocol.

Violent Encounters and Crime Scene Management

Calls involving physical violence, weapons, or civil unrest demand rigorous adherence to safety rules. An emergency medical technician must not enter a potentially violent scene until law enforcement has secured it and you have confirmed that it is safe to enter. If dispatch indicates an assault, shooting, or active domestic dispute, or if a potential crime scene may be unsafe, stage at a safe distance until law enforcement secures it and gives direct confirmation.

Scene safety is not permanent. A scene that appears peaceful on arrival can rapidly escalate into a violent or unpredictable situation. If a scene becomes unsafe at any point, withdraw to a safe location and request the appropriate assistance. Your duty to provide medical care does not supersede your obligation to protect your life and your partner's life.

When operating on a secured crime scene, medical providers must balance investigative needs with patient treatment. Preserving evidence at a crime scene is secondary to personal safety and life-saving patient care. While emergency medical technicians should be mindful of physical evidence, their primary obligation once safety is confirmed is to deliver life-saving interventions without delay.

Standard Precautions and PPE Selection

Standard precautions apply to every patient and address potential exposure to blood; body fluids, secretions, and excretions other than sweat; non-intact skin; and mucous membranes. The foundation of infection control begins with hand hygiene, which is recognized as the single most effective method for preventing the transmission of disease. Hand washing with soap and water is required when hands are visibly soiled with blood or bodily fluids. Alcohol-based hand sanitizers can be used when hands are not visibly soiled. Crucially, hand hygiene must be performed before touching a patient and immediately after removing gloves.

Personal protective equipment must be selected based on the specific clinical task and anticipated exposure. Medical examination gloves must be donned before making any contact with blood, body fluids, or non-intact skin, and exam gloves must be changed between patients to prevent cross-contamination. If medical gloves become punctured or torn, remove them promptly, perform hand hygiene, and put on new gloves. During vehicle extrication, wear appropriate cut-resistant rescue gloves, and wear medical examination gloves underneath when contact with blood or body fluids is anticipated.

When performing tasks that generate fluid splatter, additional barriers are mandatory. For example, when suctioning a patient's airway, the emergency medical technician must wear gloves, eye protection, and a mask to protect against splattering. Eye protection with side shields or a full face shield is required whenever fluid spraying or splattering is anticipated. Ordinary prescription eyeglasses do not provide adequate eye protection because they lack adequate protective coverage. Fluid-resistant gowns must be worn when substantial blood or body fluid splattering is expected.

Respiratory protection requires careful distinction between droplet and airborne pathogens. Wear a fit-tested N95 or higher-level respirator when caring for a patient with a suspected airborne infection, such as tuberculosis. Surgical masks do not protect healthcare workers against airborne droplet nuclei. Providers must undergo annual fit-testing to ensure a proper seal with an N95 respirator, and facial hair that interferes with the mask seal prevents an N95 respirator from functioning effectively. To minimize transmission from the patient, offer a coughing patient a surgical mask for source control if the patient can tolerate it, as placing a surgical mask on a coughing patient reduces droplet transmission to others.

Equipment Decontamination, Sharps, and Exposure Protocols

Infection control extends beyond direct patient contact to include the care of equipment and medical waste management. Providers must understand the operational distinction between cleaning and disinfection. Cleaning is the process of removing visible dust, dirt, and organic material from surfaces. Disinfection uses chemical agents to destroy pathogenic microorganisms on non-living objects. Reusable equipment that contacts only intact skin generally requires cleaning and low-level disinfection between patients, following the manufacturer's instructions and local protocol. Any contaminated reusable equipment must be decontaminated before being returned to active service.

Safe handling of sharps is vital to prevent accidental exposure to bloodborne pathogens. Used sharps must be disposed of promptly in approved, closable, puncture-resistant sharps containers. Needles must never be bent, broken, or recapped using a two-handed technique. In general, do not recap used needles; however, if a specific procedure makes recapping unavoidable, follow local protocol and use a one-handed scoop technique or mechanical device. Items saturated with blood or other potentially infectious materials must be disposed of in designated biohazard waste containers according to local policy.

Despite strict safety practices, accidental exposures may occur in the field. After an occupational exposure, immediately wash affected skin with soap and water, or flush exposed eyes and other mucous membranes with water or saline. Following an exposure, the emergency medical technician must promptly report the incident to the designated infection control officer to initiate documentation and appropriate medical follow-up.