Guidance [Jan 1992;21(1):19-34]
Virtually all operating room fires ignite on or in the patient, and about
10 surgical patient fires a year come to ECRI's attention through various medical and
legal communications. These fires typically result in little damage to equipment, cause
considerable injury to patients, and are a complete surprise to the staff.
other potentially disastrous fires singe linen, hair, or instruments, but are quickly
patted out and soon forgotten.
The basic elements of a fire are always present during surgery. A misstep
in procedure or a momentary lapse of caution can quickly result in a catastrophe. Slow
reaction or the use of improper fire-fighting techniques and tools can lead to damage,
destruction, or death. Given the tremendous potential for human and economic disaster
resulting from surgical patient fires, it is surprising that perioperative fire prevention
receives so little attention.
Surgical fires are preventable, and their impact can be lessened through
an understanding of fire and how to fight it. The following article identifies the basic
elements of fire and discusses how to prevent surgical fires from starting. The surgical
fire case summaries at the end of this article describe steps for putting fires out and
for preventing fires from starting by using proper procedures and techniques. ECRI has
also published Emergency Procedures, "Fighting Fires on the Surgical Patient" and
"Extinguishing Airway Fires."
Understanding the Fire Hazard
Most people have heard of the fire triangle: heat, fuel, and oxidizer.
When these three components come together in the proper proportions, a fire—the rapid
chemical reaction of fuel with oxygen, resulting in the release of heat and light
energy—is bound to occur. Diminish or remove any element of the triangle, and a fire
can be prevented or extinguished.
Each side of the triangle contains obvious (and some not-so-obvious)
components that are commonly found in the OR environment. Each member of the surgical team
controls a specific side of the triangle: surgeon, heat sources; nurse, fuels;
anesthesiologist, oxidizers. By understanding the fire triangle and how to properly manage
its components, the surgical team can prevent fires.
Heat and ignition sources.
Heat input from
a variety of sources increases the oxidation rate of a fuel-oxygen mixture until
combustion occurs. In addition to the overhead surgical lights, some of the heat
sources found in the OR are defibrillators; electrosurgical or electrocautery
units (ESUs, ECUs); heated probes; drills and burs; argon beam coagulators;
fiberoptic light sources and cables; and lasers used with the free-beam
(bare-fiber) method or with contact tips or fibers. These sources produce
temperatures from several hundred to a few thousand degrees Fahrenheit, enough
to ignite most fuels, including most drapes. In addition, incandescent sparks
can be produced by ESUs or high-speed drills and burs; lasers can also cause
sparks when the energy hits instruments or the laser fiber becomes damaged.
These sparks, or even glowing embers of charred tissue, can provide enough
initial heat to ignite some fuels, especially in oxygen-enriched atmospheres
Also, for a few seconds after deactivation, a heated ESU or ECU probe tip,
fiberoptic cable tip, or laser contact tip can retain enough heat to melt plastics or
ignite some fuels. While these devices must be in contact with a material to heat it, a
laser can heat a fuel from a few centimeters to several meters away. A fiberoptic light
source may take a minute or so to heat a drape to the point of combustion, while a laser
can cause almost instantaneous ignition. By ensuring that these heat sources are not
directed toward or allowed to come in contact with fuels, OR staff can prevent fires.
A fuel is anything that can burn, including almost everything that comes
in contact with patients, as well as the patients themselves. As shown in the "Fuels
Commonly Encountered in Surgery" table below, fuels abound in the OR; note that, in
addition to the many items that are generally known to burn, many other items that are not generally thought of as flammable are listed.
Some prepping agents and a few ointments required during surgery are
volatile and extremely flammable, more so than many other fuels. For example, liquid
alcohol from a wet, dripping prep can pool under the patient and generate vapors beneath
the drapes for quite some time. Concentrated alcohol vapors trapped under drapes or above
areas still wet with alcohol can be easily ignited by heat or sparks (see "Proper
Prepping Techniques," below). Open bottles or basins containing volatile solutions
(e.g., alcohol from suture packs, acetone degreaser) should be closed or removed from the
sterile area as soon as possible after use.
Under the right conditions, some surgical ointments can burn. For example,
petroleum-based ointments used in an OEA will ignite when enough heat is present to cause
vaporization. These materials must vaporize and mix with oxygen to allow ignition. Globs
of ointment are not easy to ignite because their mass absorbs considerable heat before
vaporizing. Thin layers, however, have a low mass per area and need less heat to cause
vaporization; thus, they are more ignitable.
In contrast, water-based lubricants, such as K-Y Jelly, are mostly water
and will not burn; heat simply vaporizes the water in the lubricant, cooling the area. In
fact, water-based lubricants can be used to coat hair to make it fire resistant.
Fuels Commonly Encountered in Surgery
Hair (face, scalp, body)
GI tract gases (mostly methane)
Degreasers (ether, acetone)
Alcohol (also in suture packets)
Tinctures (Hibitane [chlorhexidine digluconate], Merthiolate
[thimerosal]), DuraPrep [idophor])
Drapes (woven, nonwoven,
Gowns (reusable, disposable)
Hoods and caps
Instrument and equipment drapes and covers
Mattresses and pillows
Adhesive tape (cloth, plastic, paper)
Collodion (mixture of pyroxylin, ether, and alcohol)
Petrolatum (petroleum jelly)
Tincture of Benzoin (74% to 80% alcohol)
Aerosols (e.g., Aeroplast)
(breathing circuits, masks, airways, tracheal tubes, suction catheters, pledgets)
Coverings of fiberoptic cables and wires (e.g., ESU leads, ECG leads)
Blood pressure and tourniquet
Disposable packaging materials (paper, plastic, cardboard)
Smoke evacuator hoses
Some instrument boxes and cabinets
Most fuels burn only in the
gaseous state and ignite only when sufficient vapors have mixed with oxygen.
Heat produces these vapors by evaporating liquids or vaporizing solids. Although
oxygen from the air combines with fuels during a fire, the OR has other sources
of oxygen. (Also see "Oxygen Supply-System Fires," below). Anesthesia
often requires delivering oxygen-enriched mixtures above the 21% oxygen of room
air to ensure proper oxygenation of the patient. (Whenever and wherever the
oxygen concentration is above 21%, an OEA exists.) This oxygen is supplied from
the anesthesia machine, ventilator, wall outlet, or gas cylinder. Because oxygen
is heavier than air, it collects in low-lying areas (e.g., open chest cavity,
drape folds). Some materials, such as some drape fabrics, absorb oxygen and
retain it for some time (see below). With increased oxygen, a fire is easier to
ignite, will burn faster and hotter, and will be more difficult to extinguish.
An OEA will also allow some materials (e.g., many plastics) to burn that will
not burn in room air.
Oxygen for a fire can also be supplied from the thermal decomposition of
nitrous oxide. Heat from sources found in the OR or a fire liberates oxygen from nitrous
oxide, allowing it to support combustion. Thus, within the context of surgical fires, any
mixture of oxygen and nitrous oxide should be considered an OEA. In the event of a fire,
the supply of nitrous oxide, as well as oxygen, must be shut off quickly to reduce the
intensity of the fire.
Proper Prepping Techniques
Alcohol is extremely flammable and is found in many forms in the OR. An
explosive fireball from alcohol vapors ignited by an ESU, laser, or other heat source has
enough force to knock down the surgical team and start an extensive fire. Prevention
factors include minimizing liquid alcohol solutions in pools around the patient or in open
containers, allowing thorough drying of applied solutions before draping, and ensuring
dissipation or dilution of alcohol vapors before using any heat source near the patient.
For example, when a patient is prepped, the prepping solution should be
applied with minimal dripping to avoid forming pools of liquid on, under, or around the
body. Paint-stick and gauze-prep application are typically drippy, whereas a
reservoir-type applicator helps to minimize dripping. Any pools that do form, especially
in the umbilicus and cricoid notch, should be blotted. Nonflammable, water-based (e.g.,
Soloprep, Betadine, Pharmaseal) preps should be used when appropriate. The completed prep
must be visibly dry before draping; this may take 2 to 3 min, as recommended by one
manufacturer, or as long as 10 min with other solutions and application techniques. A
completely dry prep ensures that potentially flammable alcohol vapors will not be trapped
beneath the drapes. Only then can an ESU or laser be used without fear of igniting the
Oxygen Supply-System Fires
Probably the least likely but potentially most disastrous fire hazard in a
medical facility is the oxygen-supply system. Such a system can be a bulk liquid-oxygen
plant that supplies gaseous oxygen to the entire hospital or a simple gas cylinder with a
regulator that supplies a single patient. While these systems must meet certain design,
inspection, and usage requirements, fires still occur, chiefly because they have been
repaired or modified in violation of the governing codes (e.g., NFPA-99; see References
Large liquid-oxygen plants must be located outside of the hospital and
away from flammable materials. However, at many sites, direct connections are made to the
hospital to provide electricity or other utilities to the bulk facility. Modifications of
these connections in the bulk facility with non-oxygen-approved hardware can allow liquid
oxygen to enter the hospital unexpectedly. Catastrophic fires in the hospital can result,
as these utilities usually terminate in machinery rooms or other low-traffic areas of the
Frequently, leaking seals in oxygen systems are really cases of adiabatic
compression ignition of the seats and seals of a valve that is not designed for oxygen
use. When oxygen is allowed to flow from a high-pressure into a low-pressure volume, the
recompression of the gas in the piping system can cause a rapid rise in gas
temperature—up to 1,700° F. Certain materials cannot
withstand both 100% oxygen and high temperature and are quickly ignited and burned away.
Their products of combustion are sometimes carried in the oxygen stream and can cause
injury to patients some distance from the valve. If the valve body is also incompatible
with oxygen use, it too can ignite and burn in a kindling chain of ignition when the
burning seats and seals provide enough heat to burn the metal.
Improper assembly of high-pressure oxygen regulators has resulted in
several fires. In these cases, it is thought that pieces of Teflon tape, chips from seal
materials, or latent hydrocarbon contamination was present in the high-pressure section of
the regulators. Rapidly opening the oxygen cylinder caused adiabatic compression ignition
of this material, which, in turn, ignited O-ring seals and then the aluminum regulator
Other Aspects of Fire
The fire's intensity.
When a heat source,
a fuel, and an oxidizer combine to produce a fire, the characteristics of the
fire—such as burning rate, heat generated, and size—define the
fire's intensity and depend on certain traits of the components of the fire
triangle—such as heat input; fuel type, composition, geometry, and
orientation; and oxygen environment. For example, a thick drape will burn a bit
slower than a thin drape because it has greater mass to heat, ignite, and burn.
When horizontal, a drape will burn slowly in air with the flame front spreading
slowly out from the ignition point; when vertical, buoyant convection of the hot
gases makes the fire spread quickly upward with large amounts of flame. If an
OEA is added to the scenario, the drape will explosively burn with a large and
rapidly expanding flame front. Generally, the more oxygen available, the larger,
hotter, and faster a fire will burn (see "Laser Ignition of Surgical
Products of combustion.
If a fire burns a fuel completely, it will convert the fuel into various
oxides (e.g., water, CO2, nitrogen dioxide). However, most fires are
not that simple: a complex collection of numerous molecules is produced
depending on the fire's temperature; the fuel type, chemical composition, shape,
and orientation; the available oxygen; and various other factors. For example,
incomplete combustion will produce partially oxidized molecules such as toxic
carbon monoxide, acidic free hydrogen, and unburned carbon or soot. In general,
a fire will produce any and all combinations of the basic elements and molecules
of the fuel with oxygen.
Few studies to determine the combustion products of specific materials
have been performed, but those to date show that plastics produce the most toxic
combustion products. Plastics are basically hydrocarbons with various other elements added
to create special properties. These elements cause burning plastic to produce toxic
chemicals such as hydrogen chloride, hydrogen fluoride, cyanide, mustard gas, phenol,
aldehydes, and other complex hydrocarbons. These chemicals can cause a fire that would
asphyxiate victims before burning them to death. In fact, most fire deaths in the United
States are caused by asphyxiation.
Preventing, Preparing for, and Managing Surgical Fires
The following discussion will help the surgical team learn how to prevent
fires by controlling each aspect of the fire triangle; to develop a fire plan covering
fire drills and fire extinguishers; and to manage fires that occur on or in the patient.
Preventing Fires: Disrupting the Fire
The most obvious and easiest method of fighting fires is to prevent
them from starting, primarily by developing an understanding of the fire triangle.
Staff can learn how to prevent its three elements from combining in the OR by controlling
heat sources, especially by following laser and ESU safety practices; by managing fuels,
particularly by allowing sufficient time for patient prep; and by minimizing oxygen
concentration through judicious use of oxygen and tenting drapes. Although devices and
methods exist to minimize the risk of completing the fire triangle during surgery, they
have to be consistently used to be effective.
Controlling heat sources.
preventing fires involving surgical patients is controlling the various heat
sources in the OR and preventing them from contacting fuels. Most OR fires are
started because a heat source was not safely or properly used. Vigilance on the
part of everyone in the OR is needed to keep this part of the triangle from
creating a fire. Many heat-generating or energy-producing devices sound a tone
when the device is in use; an activation tone that sounds during periods when
the device is not being used should alert the surgical team to deactivate the
unit and check for a fire. Laser safety protocols are designed to ensure that
the laser is in Standby mode and is inactive whenever the laser tip is not
within the surgical field. Removing unneeded footswitches will prevent
accidental device activation and a possible fire.
Using wet, sterile towels; wet pledgets; or nonflammable drapes around the
laser surgical site can prevent an errant beam from igniting the drapes near the site.
Although sterile water keeps the material cool and excludes oxygen, preventing ignition,
care must be taken to prevent violating sterile procedure when wetting areas near the
surgical site; however, once a fire occurs, infection control takes second place to
controlling the fire.
When used, an ESU holster prevents the accidental arcing of the probe tip
and keeps it sterile and safe. Keeping the probe tip clean minimizes the risk of adherent
tissue incandescing or flaming. Taking the time to allow a hot instrument to cool near its
point of use will prevent it from igniting nearby drapes, gowns, tubing, or other fuels.
The proper use of special devices, such as LRTTs or jet ventilation, will also reduce the
risk of airway fires.
Allotting sufficient time
after patient prepping before draping allows vapors and gases to dissipate. As
discussed earlier, where volatile liquid (e.g., alcohol) exists, so does the
risk of fire. Volatile fuels, such as alcohol, collodion, and acetone, can take
several minutes to fully vaporize and a few minutes more to become diluted in
room air. Care should be taken to avoid or minimize pooling of volatile liquids,
including under the patient where they may not be noticed. Taking the time to
check that these volatile fuels have fully evaporated on and under the point of
application will prevent them from being ignited. Also, allowing high
concentrations of oxygen to dissipate will reduce the ignition risk of most
Minimizing oxygen concentration.
Minimizing the concentration of oxidizers during surgery by checking for
open sources of oxygen will also reduce the risk of fire. As discussed above,
high oxygen concentration, including the oxygen contributed by nitrous oxide,
will enhance the ignitability of most fuels; minimizing the percentage of oxygen
flowing around the patient will reduce the fire risk. For many surgical
patients, this can be done by using room air, oxygen diluted with an inert gas,
gas scavenging, or a circle breathing system. If an open oxygen source must be
used, the drapes must be tented around the patient's head to allow air
circulation to dilute the additional oxygen. With an outlet, gravity will assist
in pulling oxygen to the floor away from the patient.
As noted above, judicious use of oxygen can also minimize oxygen
concentration. For example, not every patient needing head-and-neck surgery requires 100%
oxygen; room air or a low concentration of oxygen balanced by an inert gas (e.g.,
nitrogen, helium) may be adequate for ventilation and thus reduce the fuel-ignition risk.
Alternatively, controlled and selective use of 100% oxygen during periods of low fire
risk, such as when no ignition sources are in use, will reduce the fire risk; however,
time must be allotted for the OEA to return to ambient levels. These precautions are
especially useful during head-and-neck surgery, where the risk of fire is increased
because of the proximity of a heat source, fuels, and an oxygen source.
Preparing for Fires: Developing a Fire
Conducting fire drills.
Being prepared for a fire is inexpensive insurance that will minimize the
cost in dollars, lost time, emotional shock, and injury or death. Preparation involves a
number of steps—the most important of which is practicing fire drills that teach all
staff about their responsibilities during a fire. Although many facilities, in compliance
with Joint Commission on Accreditation of Healthcare Organizations (JCAHO) requirements
(see References and Resources), conduct drills for evacuating the OR in the event of a
major fire, drills for the surgical team for fighting fires involving the patient are
rare—and should not be.
Hospitals are required to have a plan for fires and to practice this plan
at regular intervals so that all staff members on all shifts are familiar with the proper
response to a fire emergency. Although meeting fire-safety requirements in an effective,
realistic, and capable manner is difficult because of the myriad demands on the OR staff,
having a preplanned method of fighting a surgical fire so that every team member knows
what to do is critically important. Practice should account for the inevitable problems
that arise during emergencies, such as exits that are blocked, equipment that is not
working, rooms that are crowded with people and equipment, and surgical tables that are
difficult to move.
The staff must especially practice drills for fires on and in the patient
(see ECRI's "Emergency Procedures: Fighting Fires on the Surgical Patient").
- keeping minor fires from getting out of control;
- managing fires that do get out of control;
- the location and proper use of fire-fighting tools;
medical gas valves; heating, ventilation, and air-conditioning (HVAC)
controls; and electrical supply switches; and
- the fire alarm and communication system.
All fires start small. Surgical teams should be trained in and practice
drills for quickly stopping small fires that involve drapes, gauze, ointments, and
liquids. But fires move quickly—slow reactions or confusion can allow a small fire to
become a large, more dangerous one. Large fires especially require special drilling to
develop the team effort needed to deal with sizable volumes of flame and smoke, as well as
burning drapes and plastic in the small space of an OR. The use of fire-fighting equipment
for rescue and escape should be explained and demonstrated. Fire extinguishers, discussed
in detail below, are critical to managing fires, and staff must be trained in their proper
use. Drills should also identify the location of medical gas, ventilation, and electrical
systems and controls, as well as when, where, and how to shut off these systems. The
fire-containment design and construction of most hospitals helps to ensure that the staff
has enough time to evacuate other patients and staff. The use of the hospital's alarm
system and system for contacting the local fire department should also be defined.
Using Fire Extinguishers
Types of Extinguishers and Agents
Fire extinguishers are classified according to National Fire Protection
Association (NFPA) standards as illustrated below.
For wood, paper, cloth, and most
For flammable liquids or
For energized electrical
The various types of fire extinguishers available to fight each class of
fire are described below. Knowing how these devices work and when to use them will
minimize the disaster of an OR or surgical patient fire.
Carbon dioxide. A 5 lb carbon dioxide (CO2) fire
extinguisher is the best choice for putting out fires typically encountered in
ORs—where the patient is the primary concern. Despite their Class BC rating, CO2
extinguishers can be used to extinguish small masses of cloth, plastic, or paper (Class A)
involved in patient fires, as well as any flammable liquid (Class B) or electrically
energized (Class C) fires that could occur in the OR. Equally important, these
extinguishers do not leave residue and will not harm the patient, staff, or equipment. A 5
lb capacity CO2 extinguisher weighs approximately 7 to 9 kg (15 to 20 lb), fits in
a space approximately 23 x 23 x 36 cm (9 x 9 x 14 in), and is easily handled by
most people. For easy access, the extinguisher should be mounted inside the OR
near the entrance.
Dry powder. Class ABC-rated fire extinguishers are not
appropriate for use in the OR. These models disperse a cloud of fine, dry powder (usually
ammonium phosphate) that extinguishes the fire. This cloud contaminates all surfaces in
the OR, including the patient and any surgical wounds. In addition, the powder is a
respiratory irritant, which could affect the staff's ability to aid the patient, is hard
to remove from wounds, and requires that all contaminated equipment be thoroughly cleaned.
While dry powder extinguishers should be available in the OR suite (outside
individual ORs), they should be used in the OR only as a last
Halon. Halon extinguishers, which are no longer available because of
environmental concerns, had been a better choice for use in the OR than CO2 extinguishers. These units
have a unique fire extinguishing action and a low weight, making them easy to
use. Halon extinguishers that are still in service will continue to provide
protection; however, once used, they cannot be recharged.
Water. Pressurized-water (PW) fire extinguishers are available, but
they are heavy and are chiefly effective against Class A fires. Using a PW extinguisher is
more difficult than using a Halon or CO2 device. To extinguish burning
water-repellent drapes with a PW fire extinguisher, users must place a finger
partially over the end of the nozzle to produce a fine spray. Water in a stream
or tossed from a pan can fan the flames and increase a drape fire. Water from
corridor-located fire hoses typically spray 50 gallons of water a minute and can
be effective as a last resort when immediate rescue or evacuation is needed.
Water as a fire-extinguishing agent can be used over a wide range of
fires. However, a fire involving energized electrical equipment, although rare in the OR,
should not be extinguished with water, but with an extinguisher rated for Class C fires.
In order to do any job properly, the right tools—particularly, fire
extinguishers—must be available and used in the correct manner. The staff should be
instructed and become experienced in their use to fight fires; if improperly used, a fire
extinguisher can create more problems then it solves.
Often, local fire departments can provide the staff with hands-on practice
in extinguishing real fires using the equipment available in the OR. This helps build the
familiarity and confidence needed to use these devices in a frightening and hectic
situation. Fire extinguishers should be small enough to be easily carried and handled by
the most likely users, and they should be located in plain view in positions of easy
access—near escape routes, but away from fire-hazardous areas.
Most fire extinguishers are operated according to the following procedure,
whose steps are abbreviated by the acronym "PASS" (however, potential users
should be instructed in the proper use of each fire extinguisher because procedures
other than PASS may be required):
- Pull the activation pin.
- Aim the nozzle at the base of the fire.
- Squeeze the handle to release the extinguishing
- Sweep the stream over the base of the
Managing Fires: What to do if the Worst
If the patient is on fire.
Most fires in the OR will be either on or in the patient. In either case, quick action will avert a disaster.
Smoke, the smell of fire, or a flash of heat or flame should prompt a fast
response. In 30 sec or so, about the time it takes to read this and the next
paragraph, a small fire can progress to a life-threatening large fire. During
any fire, protecting the patient is the primary responsibility of the staff;
self-protection is a secondary consideration.
To contain the flames, the fire triangle must be disrupted by diminishing
or removing one or all of its sides. For example, a small area of burning drape or gown
can be patted out effectively and safely by hand; larger areas can be smothered
effectively with a fire blanket or towel. Fires inside the patient are typically
small, but can be deadly. Practicing for an airway fire, such as from a burning tracheal
tube (see the Evaluation of LRTTs (Jan 1992;21(1):4-13.), can develop the speed that will
minimize the resulting injury in a real emergency.
Good communication among the surgical team can ensure fire-safe practices; stopping small
fires before they become big fires or preventing them altogether requires a team effort.
For example, the anesthesiologist stops the gases while the surgeon and nurses put
out the fire, and then the surgical team cares for the patient. ECRI's Emergency Procedures
Checklist contains three basic steps to take in the event of a fire on or
in the patient that should be done in rapid succession, taking no more than a few seconds: 1)
stopping the flow of breathing gases to the patient, 2) removing the burning material from
on or in the patient, and 3) caring for the patient. ECRI has also prepared another Emergency
Procedures Checklist, "Extinguishing Airway Fires," that outlines procedures to
take if the source of the fire is the tracheal tube.
Oxidizers (i.e., oxygen and nitrous oxide) are often involved or become
involved in surgical patient fires. Stopping the flow of oxidizers to the patient reduces
the intensity of the fire, enabling it to be more easily controlled and extinguishing some
fires. While seemingly contrary to the goal of protecting the patient, patients can
usually tolerate short periods of air deprivation; a fire poses an immediate risk to the
patient's life, as well as to staff and other patients in the area. Burning materials on
or in the patient must be removed and extinguished immediately before they cause thermal
injury to the patient and become difficult to extinguish. Removing these materials
minimizes the injury and enables the fire to be put out safely and quickly. When the
situation is controlled, the patient must be quickly cared for by extinguishing any
residual fires, resuming ventilation, controlling bleeding, and dealing with any further
If the fire spreads beyond the patient.
addition to ensuring the patient's immediate safety, as outlined above, staff
should be aware of general guidelines and procedures for containing small fires
and effectively managing large fires that have somehow gotten out of control, as
illustrated below. Again, fire drills should prepare staff for the
worst—so that the worst won't happen.
Other staff should be alerted to the fire in case it gets out
of control; then, the OR staff should act to control the flames. The oxygen and nitrous oxide
flow to the patient should be interrupted, and fuels should be either removed from
the fire's environment or prevented from vaporizing (e.g., by pulling apart a set of
burning drapes) to separate the fuel from the fire. A nonflammable material, such as a wet
towel or sterile saline, can be used to cool the fire. Water or inert gases from
a fire extinguisher can be directed at the flames—a squirt of CO2 (or Halon) will
knock out a drape fire with minimal contamination of, and secondary damage to, the
patient. Other tools, such as fire blankets, can be used to control some flames. Any
electrical device involved in the fire should be unplugged. If the fire does start to get
out of control, the fire department should be notified to give firefighters ample time to
respond; firefighters would rather find that a small fire has been extinguished than see
smoke billowing out of a building—especially a hospital.
If these measures are not taken or are not effective, staff must know what
to do in the event of a large fire. In such cases, gases supplied to the patient can
accelerate flame propagation. Toxic smoke will form a hot, dense layer near the ceiling,
obliterating overhead lights. The smoke can migrate through the room ventilation system.
Staff should keep low and quickly get and use fire extinguishers, perhaps the only hope at
this point—although sprinklers, in ORs so equipped, may open and room ventilation may
also automatically shut down to prevent smoke from entering other areas. If the fire
department has not been notified, this should be done now.
The patient should be evacuated on the operating table if possible. The
oxygen and nitrous oxide to the burning OR should be shut off to prevent reignition of the
fire, as should electricity if equipment is involved or water is used to extinguish the
flames. Electrically energized equipment doused with water can be hazardous to personnel.
If the fire progresses past 1 min, the entire operating suite should be evacuated.
Although the possibility of fireball explosions from bottled alcohol or gas cylinders is
extremely remote, such accidents can happen. By this time, the fire department should be
responding, and other surgical teams should be preparing their patients for immediate
removal from the danger area. The burning OR must be closed to reduce the spread of smoke
and fire. The building fire hose will apply many gallons of water per minute and can be
effectively used to rescue injured or unconscious patients or staff in a major fire.
Reporting Surgical Fires—The Legal Requirements
Many states and some professional organizations have regulations or
standards requiring hospitals to report fires to their local fire department. For example,
the Pennsylvania Department of Health, in its Rules and Regulations for Hospitals, states
that "every building should have an automatic and manually activated fire alarm
system installed to transmit an alarm automatically to the fire department by the most
direct and reliable method approved by local regulations." Many state and local
regulations refer to codes and standards written by NFPA. NFPA 101, Code for Safety to
Life from Fire in Buildings and Structures, requires an alarm system that, when activated,
will automatically notify the fire department. In NFPA 99, Standard for Health Care
Facilities, the steps to take in the event of a fire are detailed, including notification
of the fire department. Thus, if these codes are followed, an alarm set off in the
hospital will automatically notify the local fire department.
Other organizations, including JCAHO and, in some states, the department
of health, also require hospitals to document fires. For example, JCAHO states in its Accreditation
Manual for Hospitals that, at the time of its survey, hospitals must have
"records of actual fire incidents." New York regulations require hospitals to
report "fires in the facility which disrupt the provision of patient care services or
cause harm to patients or staff within 24 hours to the state health department."
Written follow-up reports are also required. The New Jersey Department of Health, in its
"Licensing Standards for Hospitals," states that "there must be a system in
place for reporting and investigating fires." Thus, it is important to know the
Failure to comply with a statute or safety regulation has legal
ramifications: a violation may be considered negligence per se. The standards or
guidelines issued by professional or accreditation organizations, such as JCAHO, do not
have the force of law. Nevertheless, they may be used as evidence of the standard of care
that a hospital must meet. Thus, from a risk management point of view, the safest course
is to notify the fire department and keep records of any fire in your hospital. Clinical
department heads should notify the safety officer, hospital risk manager, and/or hospital
administrator in the event of a fire.
Also, the event should be analyzed to determine whether it must be
reported to FDA under the Safe Medical Devices Act (SMDA) of 1990. For example, in the
case of a laser-related injury to a patient, a report would be required. This issue should
be discussed with the hospital's risk manager.
Surgical Fire Case Summaries
Examples of specific cases that illustrate the variety of and ease with
which surgical patient fires happen are discussed below. Tips on how these fires could
have been prevented are also given. Most of these are drawn from our investigation of
specific incidents. These examples are listed in groups according to the primary causative
factors (aspects of the fire triangle) that were involved in each case.
ESU/ECU, Improper Procedure
- Heat source—ESU
- Fuel—Bowel gas (methane) due to improper
A methane-producing diet and improper cleansing of the bowel before
surgery led to a bowel explosion. Without first venting the bowel, the surgeon exposed the
colon and proceeded to enter it using an ESU. The hot ESU tip caused the explosive
ignition of the bowel gases, which caused a 10 cm tear of the colon. The patient was
otherwise uninjured and subsequently recovered.
Fire in incision site:
- Oxidizer—100% O2
The use of a dry gauze pad in an OEA led to a fire in the incision site. A
gauze pad was placed in the incision site during a lung resection. The dry pad was being
used to blot blood from the tissues. At the time the fire occurred, an ESU was being used
to cauterize a bleeder immediately next to the gauze. The lung lobe had already been
resected, and oxygen was flowing out of the resection area, enriching the operative site
itself. The oxygen, in turn, enriched the gauze and allowed it to be easily ignited by the
ESU. The burning gauze pad was thrown to the floor and extinguished without any apparent
injury to the patient.
Flash fire of eyelid:
- Oxidizer—O2 and N2O
An unrecognized fuel- and oxygen-enriched atmosphere set the stage for
this flash fire. Skin lesions were being removed from the patient's eyelid and neck.
General anesthesia was administered by mask and was maintained with a 2:3 oxygen:nitrous
oxide mixture and a small amount of halogenated anesthetic. An ophthalmic ointment was
applied to the eyes. When the surgeon used an ECU to remove a mole on the eyelid, a flash
fire occurred. Quick control of the fire limited the patient's injury to only minor burns.
The patient recovered without incident.
ESU/ECU, Drapes, Improper
A straightforward breach of infection control and surgical technique led
to this fire. During emergency surgery, a contaminated ESU pencil was not removed or
placed in a protective holster, but was allowed to dangle over the side of the operating
table. An OR nurse unknowingly leaned against the pencil, causing it to activate, arc
through the drapes to an instrument table, and ignite the drapes. The flame spread rapidly
up the drapes vertically from the ignition point about 2 ft off the floor and onto the
patient. By this time, the fire was burning with such intensity that all other flammable
materials on and around the patient were easily ignited and quickly burned. The patient
died, but it is not certain whether the cause of death was the fire or the initial
- Fuel—Gauze, drapes
Use of a dry gauze pad to clean the ECU tip led to this fire. A quick
response by the surgical team minimized the injury to the patient undergoing cervical
cauterization. Disposable drapes were being used on the patient, who was in the lithotomy
position. The surgeon routinely cleaned the ECU tip with a dry gauze pad. Frequently
throughout the procedure, the dry gauze pad ignited (wet gauze would not have ignited),
and the doctor threw the burning pad to the floor and stamped it out with his foot. In one
instance, he threw a burning gauze pad to the floor, and it ignited the bottom edge of the
vertically hanging legging drape on the left leg. Within approximately 7 sec, the fire had
rapidly spread up the drape. The drapes were pulled off the patient as they were burning;
however, the patient sustained severe burns on the left leg.
ESU/ECU, Oxygen, Improper
Fatal tracheal tube fire:
- Fuel—Tracheal tube
- Oxidizer—100% O2
Ignition of a tracheal tube during a tracheostomy resulted when a surgeon
used an ESU too aggressively. With the ESU in the Coagulation mode, he attempted to cut
through the cartilage rings of the trachea. In doing so, he ignited the tracheal tube
cuff, which started the plastic tube burning in the presence of 100% oxygen. The surgical
team, which was slow to recognize that the fire was in the airway, gave three breaths of
100% oxygen while trying to extinguish the fire. Each breath reignited the smoldering
tracheal tube. The patient died several weeks later because of injures from the fire. ESUs
should NOT be used to enter the airway, especially with 100% oxygen and a plastic tracheal
Had the surgical team realized that there was an airway fire, reacted
quickly, and not given the breaths while trying to extinguish the fire, the patient may
have suffered only minor burns.
- Heat—ESU, tissue ember
Gauze that was initially wet, but that dried out and became oxygen
enriched during a procedure, led to this throat fire. Surgery was being performed under
general anesthesia in the back of the throat of a patient with a tracheal tube. The area
above the tube cuff had been packed with wet gauze. The gauze dried out during the course
of surgery and became oxygen enriched because of a minor leak around the cuff. During use
of an ESU, a glowing ember of charred tissue floated down into the back of the patient's
throat, ignited the gauze, and caused flames to briefly erupt from the patient's mouth.
The patient sustained minor burns and subsequently recovered. Had the gauze been checked
and kept wet, the fire would probably not have occurred.
ESU/ECU, Oxygen, Drapes
- Fuel—Drape fibers or body hair
- Oxidizer—100% O2
The creation of an OEA, caused by an open oxygen source, allowed this fire
to occur. A patient was having several skin lesions removed from her right breast. She had
been given a tranquilizer and was being given oxygen with a face mask at a flow rate of
approximately 4 L/min. The surgeon had initially removed a lesion from her neck without
incident. The drape fenestration was then slid down toward her right breast. This area was
prepped in the usual fashion with povidone-iodine, and the incision site was anesthetized
with a local anesthetic. During use of the ESU, the surgeon stated that a spark flew from
the operative site over toward the edge of the surgical drape. This coincided with a cry
from the patient.
The method of flame propagation in this case is not absolutely clear, but
surface-fiber flame propagation was involved. Two possibilities are likely: 1) the nap
fibers on the reusable drape burned, or 2) the patient's fine body hair burned and
rapidly spread the fire under the surface of the drape up toward the patient's face. The
fire then ignited the oxygen mask and resulted in some minor burns to the patient's face
and neck. In either case, the presence of the open oxygen source and the oxygen wafting
out of the fenestration was the predisposing factor to the fire.
- Oxidizer—100% O2
In another drape fire involving an OEA, quick action by the surgeon and
anesthesiologist resulted in minimal injury. The surgeon was operating through a
microscope on a patient's eye. He asked for a disposable cautery pencil to cauterize a
bleeder and was given a device with a 2-inch shaft rather than the ½ -inch shaft he was
accustomed to using. He could not see that he had been given the wrong instrument because
he was using the operating microscope. He turned the cauterizer on at the instant that the
pencil was handed to him so that it would be hot at the time it reached the operative site
As the device approached the operative site, the now red-hot tip of the
cauterizer grazed the drapes over the patient's nose. Oxygen was being delivered through a
nasal cannula at a rate of 3 L/min. When the cauterizer touched the drapes, a large ball
of flame erupted on the patient's face. In a startle reaction, the surgeon scratched the
patient's cornea with the red-hot cauterizing probe. The patient was also burned along the
right nostril and right orbit. When the fireball occurred, the anesthesiologist
immediately turned off the oxygen, and the surgeon ripped the drapes off the patient's
face. Their actions minimized injuries to the patient.
Laser, Drapes, Improper
In both of the following cases, the fires would not have happened if
proper laser safety protocols had been practiced. Laser safety protocols require that the
laser be set to the Standby or Deactivated mode whenever the handpiece is out of the
surgical field. An audible activation indicator may avoid or minimize such incidents.
With the patient in the lithotomy position, the surgeon used a laser to
cauterize cervical polyps, then placed the laser handpiece against the patient's left
thigh pointing toward her left buttock. The surgeon slid the laser footswitch out of the
way with a foot just a moment before the laser nurse placed the laser in Standby mode.
Unbeknownst to surgical personnel, the surgeon had accidentally activated the laser during
The laser penetrated the outer drapes, which did not ignite because of the
flow of clearing gas from the handpiece, and ignited a dry area of the absorbent towels
under the patient's left buttock. The fire burned slowly for a minute or two, concealed by
the outer drapes; subsequently, flames erupted from the legging drapes. The patient
suffered significant burns to her left inner thigh.
A similar case during abdominal surgery resulted in laser ignition of the
patient's gown in the area of the left axilla and significant burns to her left arm.
Facial hair fire:
- Heat—Bur spark
- Oxidizer—O2 and N2O
An OEA, created by the presence of oxygen and nitrous oxide,
allowed easy ignition of facial hair. A patient was undergoing maxillofacial surgery with
general anesthesia maintained through a nose mask with a concentration of 25% oxygen, 75%
nitrous oxide, and a small percentage of halogenated anesthetic. The patient had a
moustache. As the surgeon was grinding a filling with a tungsten-carbide bur, an
incandescent spark flew from the bur and arced out of the patient's mouth, over his upper
lip, and landed in his moustache. Because of the high concentration of oxygen, effectively
50% because of the nitrous oxide, the moustache immediately burst into flame and ignited
the nasal mask. The fire then flashed back toward the anesthesia machine along the gas
delivery hoses. As soon as the fire was noticed, the nasal mask was removed from the
patient's face, but not before significant burning of his nose and upper lip had occurred.
Had a water-based lubricant been used to coat the moustache hair, the spark would not have
caused the fire.
General equipment fires:
In ECRI's nearly 30 years of investigating OR fires, equipment fires have
been extremely rare, probably because of strict electrical safety standards, good design
of equipment, and routine inspection and preventive maintenance. One fire occurred at a
wall outlet and was handled by removing the plug from the socket. Another more serious
fire involved a transformer bank that actually burned and required the evacuation of the
patient and staff from the specialized OR.
Most "fires" in equipment are actually short circuits or
electrical overloads. They create an odor, some vapors, and are controlled by stopping the
flow of electricity to the device.
Surgical patient fires, while infrequent, can be disastrous. The vigilance
of the surgical teams in preventing the three sides of the fire triangle—heat, fuel,
and oxidizer—from combining into a fire is the best defense against a fire involving
the patient. Having, understanding, and following special procedures for dealing with heat
sources and flammable substances in the OR can reduce the fire risk. Having a fire plan
and practicing it with fire drills and training should be part of the hospital's ongoing
routine. Should a fire occur, quick and knowledgeable reaction by the staff will minimize
its impact. Unfortunately, it sometimes takes a real fire to spur a hospital to become
It is up to the individual hospital to tailor a plan to meet its specific
needs. ECRI and many other organizations and sources can help hospitals develop a
fire-protection plan. State fire marshals and local fire-fighting associations are usually
happy to work with hospitals on fire issues. In addition to NFPA, the the American Society for Testing
and Materials (ASTM), training materials producers, and manufacturers can provide
videos, films, and other teaching materials about OR fires (see References and Resources).
References and Resources
American Society of Testing and Materials. ASTM G4 committee on
flammability of materials in oxygen enriched environments. Contact ASTM: 1916 Race St.,
Philadelphia, PA 19103; (215) 299-5400.
Association of Operating Room Nurses. Standard and recommended
practices for perioperative nursing,
ECRI. Fighting airway fires. Health Devices 1990 Apr;19(4):111.
ECRI. Fires during surgery of the head and neck area. Health Devices
ECRI. OR fires: Preventing them and putting them out. Health Devices
Joint Commission on Accreditation of Healthcare Organizations. Accreditation
manual for hospitals. Chicago: JCAHO, 1991.
Medfilms Inc. Fire safety and fire extinguishers (videos). Contact
Medfilms: 6841 N. Cassim Pl., Tucson, AZ 85704-1261; (602) 575-8900.
National Fire Protection Association. NFPA 10-1988, Standard for Portable
National Fire Protection Association. NFPA 53M, Fire Hazards in Oxygen
Enriched Atmospheres, 1990 ed.
National Fire Protection Association. NFPA 99-1990, Health Care
Facilities, Section C-12.4, Suggested Procedures in the Event of a Fire or Explosion,
National Fire Protection Association. NFPA 101, Life Safety Code, 1991.
National Fire Protection Association. NFPA fire protection handbook.
16th ed. Quincy, MA: NFPA, 1986.
State and local codes applicable to healthcare facilities and fire.
* * *
Laser Ignition of Surgical Drapes
Assessing Flame Resistance
While many surgical drape manufacturers suggest, either in conversation or
in print, that their products provide protection against fire by being flame retardant or
flame resistant or that they meet this or that flammability standard, this is not
Fire tests using flames or ESU ignition sources cannot demonstrate the
susceptibility of drapes to laser ignition. Unlike a flame or an ESU, a laser emits a
concentrated beam of energy (like sunlight through a magnifying glass, but more intense)
and can thus rapidly vaporize and ignite normally flame-resistant materials. Lasers also
differ from ESUs in that they do not have to be in contact with a drape to ignite it;
whereas an ESU heats through electrical contact, the laser irradiates and can ignite a
fire with material close to the tip, at some distance from the tip, or through several
layers of material. Also, drapes can trap oxygen around the patient, creating a highly
oxygen-enriched environment; oxygen increases ignitability and flammability, and not all
flammability or flame-spread tests are done in oxygen-enriched atmospheres (OEAs).
We have investigated a number of fires involving laser ignition of
surgical drapes. In some cases, the flame was immediately seen and patted out or quickly
smothered. More serious cases occurred when the laser penetrated the outer drape and
ignited materials beneath it. These fires often burned for several minutes before being
noticed and caused serious injury to the patients. Because we are not aware of any
published scientific information regarding how a laser interacts with drape materials in
the OR, we conducted the following tests to assess drape ignitability during laser use.
Drape Ignitability Testing
We tested several kinds of drape materials to learn how they interact with
laser energy. Drapes are typically classified as disposable or reusable. Many disposable
drapes are made of cellulose fibers and some type of fiber binder or of nonwoven polymeric
fibers fused together. Reusable fabric drapes are typically cotton or cotton/polyester
blends treated with a waterproofing agent or synthetics laminated to impervious material.
(Most of these materials are described in our Evaluation of surgical drapes in Health
Devices 15, May 1986.) Because they are often used on or under surgical drapes, we
also tested an absorbent towel made of fluffy cotton with no waterproofing.
Test method. In our tests, we exposed small, dry pieces of each drape
material to CO2, Nd:YAG, KTP, and argon laser energy in air and 100%
oxygen—the best and worst flammability conditions. The laser energy was applied at
high and low power densities (e.g., 32,000 and 200 W/cm2)
until a fire occurred or for 10 sec. High power densities were obtained by using
small spot sizes (e.g., when the laser tip is close to the target). Low power
densities were obtained by using larger spot sizes (e.g., when the laser tip is
some distance from the target).
We did not use laser clearing gas (with CO2 lasers) or cooling
gas (with fiber-delivery lasers) during these tests. Gas is used, especially with older
lasers, to clear smoke from the optics and surgical site or to cool the fiber. The gas can
blow out a nascent fire in the outer drape on a surgical site, but it does not penetrate
the drape. Laser energy will penetrate the drape and act on underlying materials, possibly
causing a fire or injuring the patient.
Test results. In room air, laser energy
warmed, created a hole in, or ignited the drape. High power densities typically
vaporized the material, ignited the jet of vapor, and created a hole in the
drape in rapid sequence. Notably, the nonwoven polymeric and synthetic laminate
drapes typically melted away from the three lasers and did not burn in room air.
The cellulose-based and cotton-based drapes were typically ignited and burned in
room air by most of the lasers. Depending on the material, the flame either
continued to burn or went out when the laser stopped. With low power densities,
laser energy ignited some drapes, creating a quickly visible fire, even though
with higher power the drape was not ignited. In other cases, low laser power
density degraded the materials without igniting or caused a slight warming of
the material. Once ignited, the orientation of the drape affected how fast the
material burned; drapes burned much faster when vertical than when
In 100% oxygen, all of these materials ignited and burned with frightening
ease. High power density ignited the drapes with a loud snap. Low power density, which
only degraded the materials in room air, created fires in OEAs. Even the nonwoven
polymeric disposable drapes ignited rather than melted in 100% oxygen. The burning plastic
was especially dangerous in that it flashed over its surface and formed individually
burning beads over the area that had been covered by the drape sample. Cellulose-based
drapes burned like magician's flash paper—rapidly and with much flame and little ash.
The cotton-based fabrics burned with the slowest, but still rapid, flame spread.
An interesting phenomenon, called surface-fiber flame propagation (SFFP),
occurred with the dry absorbent towel in oxygen. The flame started at the laser impact
site and explosively spread across the surface of the towel to its edges where the flame
became established. The fine nap, or surface fibers, of the towel caused this event. The
nap was easily ignited because of its low mass, large surface area, and the ignition
enhancement of oxygen. Similarly, any material with a coating of fine fibers, even hair on
skin, can experience SFFP. Thus, frequently washed or worn drapes with raised nap can be a
greater fire hazard in OEAs.
We did not test layers of drapes or special areas of drapes, such as the
seams or the adhesive strip around the fenestration of some drapes. These conditions would
only enhance the ignitability and/or flammability of the drape system. Most adhesives are
easily vaporized and readily burn. Layers of material trap a laser beam and oxygen, retain
heat and smoke, and allow fire to smolder unseen.
Our test results are presented in the "Laser Interaction with Drapes
in Room Air" table, below. Results with specific drapes may vary depending on color,
chemical composition, and laser wavelength.
Conclusions. All drapes ignite and rapidly
burn in oxygen; thus, by minimizing the potential for an OEA near the drapes,
the chance of a laser-ignited fire will be greatly reduced. Even in room air, no
drape offers protection against a laser-ignited fire. Most lasers can ignite
cellulose-based and cotton-based drapes in room air. Polymeric and synthetic
drapes will melt away from the laser, and a high-power-density laser beam can
penetrate most drapes without igniting them; in these cases, a patient injury or
an unseen, smoldering fire could occur. Whenever a laser is used, the vigilance
of the staff in following laser safety protocols (e.g., put laser in Standby
mode as soon as it is not needed) is the best fire protection. To help minimize
risk in the case of inadvertent laser activation, a clearly audible emission
indicator should be present to alert OR personnel that the laser has been
activated and to look for a potential fire.
In light of these conclusions, drape purchasers and users should ask
questions of the drape manufacturers about the test conditions used to define the
ignitability or flammability of the drapes: What was the oxygen concentration? How was the
sample oriented? Does the treatment wash out, the color fade, or a nap form in reusable
drapes? What was the ignition source? What type of laser was used? Have the tests been
independently confirmed? Are specific test results available?
Laser Contact Tips
Some lasers use contact devices, which convert some of the laser energy
into heat at the tip. These devices present a dual ignition challenge to drapes—heat
and laser energy. Using 20 W of Nd:YAG laser energy, we pulled an active contact tip
across each of the drape materials. All of the drapes, except the nonwoven plastic, were
ignited by the contact tip and burned in room air. The nonwoven plastic melted away from
the tip. The contact tip retained heat for several seconds and was able to hole or char
all the materials after the laser was deactivated. This further points out the need for
vigilance as the best fire protection during surgery.
Laser Interaction with Drapes in Room Air*
Cellulose with Plastic Binder
Cellulose with Flame-Retardant Binder
Melted = Material became fluid with no ignition
Burned = Material was ignited by laser and continued to burn
Charred = Material became carbonized with no ignition
Holed = Laser energy created a void in the material
Jetted = Material erupted with column of flame only during laser impact
Smoldered = Material burned slowly with no visible flame
* Note: in 100% oxygen, all drapes burned.
- Burs [10-519]
- Drills [11-329]
- Electrocautery Units [11-418]
- Electrosurgical Units [11-490]
- Handpieces, Surgical [17-949]
- Light Sources, Fiberoptic [12-345]
- Lights, Surgical [12-282]