Safety & BSI (Body Substance Isolation)¶

Category: Foundations Last updated: 2026-04-05 San Juan College EMT-B Program — New Mexico

Overview¶

Scene safety and body substance isolation (BSI) are not separate topics — they are a single mindset that starts before the apparatus stops and ends after equipment is decontaminated. Safety means you come home. BSI means you do not carry a patient's illness home with you or spread it to the next patient.

The non-negotiable rule: BSI before patient contact, every time. Scene safety before stepping off the unit, every time. The two go together on the NREMT skills sheets for a reason — you cannot protect a patient if you are injured, and you cannot help anyone if you become a patient.

Body Substance Isolation (BSI)¶

BSI is the current EMS term for what medicine calls standard precautions: assume all blood and body fluids from every patient may be infectious, regardless of known diagnosis.

PPE Levels¶

PPE Item	When Required	Notes
Gloves	Every patient contact, always	Double-glove for major trauma, childbirth, or high-volume blood exposure
Eye protection (safety glasses, goggles, face shield)	Any splash risk: major bleeding, vomiting, intubation, childbirth, suctioning	A patient coughing in your face counts
Gown	Major bleeding, childbirth, significant fluid exposure	Protects clothing and skin from splash contamination
Surgical mask	Routine respiratory precautions; when patient has cough	Protects patient from you as much as you from them
N95 respirator	Suspected airborne pathogen (tuberculosis, meningitis, COVID-19, measles)	Must be fit-tested; surgical mask is not equivalent for airborne pathogens

Donning and Doffing Order¶

Donning (putting on) — gloves last: 1. Gown (if needed) 2. Mask or respirator 3. Eye protection 4. Gloves

The gloves go on last because they are your contaminated outer surface. Once gloved, touch only patient-care items.

Doffing (taking off) — gloves first: 1. Gloves (remove without touching outer glove surface — peel off turning inside-out) 2. Eye protection (remove by touching the clean sides/arms, not the front) 3. Gown (roll away from body, inside-out) 4. Mask or respirator (remove by touching straps only, not the front) 5. Hand hygiene immediately after removing each item

The principle: most contaminated items come off first; least contaminated (the mask protecting your face and airways) comes off last.

Hand Hygiene¶

Wash hands with soap and water for at least 20 seconds when visibly soiled
Alcohol-based hand sanitizer is acceptable when hands are not visibly soiled
Hand hygiene after every patient contact, even when gloves were worn
Gloves do not replace hand hygiene — gloves have microperforations and are not sterile

Scene Safety Categories¶

Before you step off the unit, visually assess the scene for hazards. The categories to check:

Traffic¶

Position the apparatus to protect the scene (blocking angle, warning lights)
Never turn your back to traffic when working a roadside scene
High-visibility vest if working in or near traffic at night or reduced visibility
US-550 and NM-371 in San Juan County: high-speed rural highways; MVCs are a leading call type

Violence / Hostile Scene¶

Look for: shouting, fighting, weapons visible, people fleeing, law enforcement already on scene
You cannot help the patient if you become a patient
Stage at a safe distance and wait for law enforcement clearance
NM law requires EMS to stage and await PD clearance before entering a scene involving violence or potential weapons
Behavioral emergencies, domestic disputes, and scenes with patients threatening self-harm require PD first

Hazmat¶

Placards, labels, odors (or no odors — nerve agents are odorless), multiple patients with similar symptoms
Stage uphill and upwind at minimum 300 feet (or per ERG distance)
Do not enter the hot zone without HazMat PPE and training
Hazmat-contaminated patients need decon before EMS care when possible
NM uses NIMS/ICS — know your role and the command structure on multi-agency scenes

Structural¶

Fire scenes: look for signs of collapse (bowstring trusses, smoke from multiple areas, walls bowing)
Floor or roof collapse risk after fire, earthquake, or structural failure
Enter only when cleared by incident command / structural authority
San Juan County: adobe and wood-frame structures; oil field facilities; trailers and manufactured homes

Electrical¶

Downed power lines: assume live until utility company says otherwise
Safe zone: at least one power-pole span away from downed line
Vehicle contact with power line: patient stays in vehicle until lines are de-energized
Do not approach without clearance from the utility

Fire¶

Smoke, flames, or fuel spill visible: do not enter without fire service clearance
Patients coming out of a burning structure: assess for CO exposure and airway burns
NM rural areas: wildfire smoke can affect multiple square miles; air quality affects crew safety too

Reading the Scene from the Apparatus¶

Before the door opens:

Slow the approach — a fast approach kills your observation. Drive past if needed.
Count what you see — patients, bystanders, vehicles, hazards
Read body language — running, fighting, weapons, or pointing toward or away from the scene
Look up — wires, structures, overhead hazards
Look down — fluids, fire, bodies on the ground that are additional patients
Ask dispatch — confirm scene information is current; update en route

The apparatus position is a tactical decision. Park past the scene on MVCs (so you approach from behind your vehicle, not into traffic). Park away from building fires. Point the cab away from the patient so you can leave fast if needed.

When to Stage vs. Enter¶

Situation	Action
Violence ongoing, weapons visible	Stage, request law enforcement, do not enter
Violence reported but no visible threat	Stage at distance; wait for PD confirmation
Hazmat with multiple patients, unknown agent	Stage uphill/upwind, activate hazmat response
Active fire	Stage outside collapse zone; wait for fire service clearance
Downed power line contacting vehicle	Stage at distance; contact utility; patient stays in vehicle
Scene declared safe by law enforcement	Enter and proceed

Once inside: If the scene becomes unsafe after entry — weapon appears, fire spreads, structure destabilizes — exit immediately, even if you are mid-treatment. You can re-enter after the scene is controlled. You cannot resume CPR if you are also a patient.

Decontamination Basics¶

EMT-B level decon:

Equipment decon: All reusable equipment wiped down with EPA-registered disinfectant after each call
Gurney: Wipe down with bleach solution (1:100 dilution) or agency-approved product after any body fluid contact
Ambulance cab: Regular wipe-down of high-touch surfaces (door handles, radio, steering wheel)
Gross decon of contaminated patient: Remove contaminated clothing; flush skin and eyes with copious water before transport if possible
Sharps: Never recap; use sharps containers; needle-stick protocol if exposure occurs

Hazmat decon (full chemical decon) requires specialized equipment and training. EMT-B does not perform hot zone decon. EMT-B receives patients post-decon at the warm/cold zone boundary.

NM Desert and Rural Context¶

San Juan County-specific hazards that appear on calls:

Rattlesnakes: Common in warm months; look before kneeling on scene; see venomous-bites
Extreme heat: Ambient temperatures in the 90s–100s°F during summer. EMT crew heat exhaustion is a real risk on outdoor scenes. Hydrate, rotate out of direct sun, and know heat illness signs in yourself.
Remote terrain: Many addresses are 20–40+ minutes from ALS backup or hospital. Scene time decisions carry more weight when transport time is long.
Oil field hazards: H2S gas (hydrogen sulfide — odor of rotten eggs at low concentration, odorless at high/fatal concentration), pressurized lines, heavy equipment, falls from height. Do not enter an oil field scene without safety officer clearance.
High-altitude effects: Farmington sits at ~5,300 feet; some calls may be at higher elevation. SpO2 values trend lower at altitude — your normal reference ranges were derived at sea level.

NREMT Relevance¶

BSI and scene safety are the first verbalizations on every NREMT skills station. The examiner is listening for:

"Body substance isolation — I'll take gloves and eye protection" (before any patient contact)
Scene safety verbalization before approaching
Identification of MOI/NOI

Failing to verbalize BSI is a critical failure on many skill stations. Say it first, every single time — not after you approach, not after you check the patient. Before.

scene-size-up — operational application of scene safety in the assessment sequence
legal-ethical — duty to act vs. obligation to not enter an unsafe scene