Journal of Clinical Anesthesia (2014) 26, 414–424

Special Article

Fires in Indian hospitals: root cause analysis andrecommendations for their prevention☆,☆☆

Kanchan Chowdhury PhD (Professor and Head of the Centre)⁎

Cryogenic Engineering Centre, Indian Institute of Technology, Kharagpur 721 302, India

Received 4 June 2013; revised 15 December 2013; accepted 26 December 2013

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Keywords:Air conditioner;Hospital fire;Oxygen;Safety;Ventilation

Abstract There is an increase in the incidence of intraoperative fire in Indian hospitals. It ishypothesized that oxygen (O2) enrichment of air, is primarily responsible for most of the fires,particularly in intensive care units. As the amount of ignition energy needed to initiate fire reduces inthe presence of higher O2 concentration, any heat or spark, may be the source of ignition when the air isO2-rich. The split air conditioner is the source of many such fires in the ICU, neonatal intensive care unit(NICU), and operating room (OR), though several other types of equipment used in hospitals havesimilar vulnerability. Indian hospitals need to make several changes in the arrangement of equipmentand practice of handling O2 gas, as well as create awareness among hospital staff, doctors, andadministrators. Recommendations for changes in system practice, which are in conformity with theNational Fire Protection Association USA, are likely to be applicable in preventing fires at hospitals inall developing countries of the world with warm climates.© 2014 Elsevier Inc. All rights reserved.

Most hospital fires generally originate from three distinct

1. Introduction

Loss of human life and property by fire is alwaysdistressing. Hospital fire happens with alarming frequencyand potentially devastating consequences in hospitals aroundthe world. Fire may be initiated in a hospital for the mostordinary reasons, such as electrical short circuit, heating dueto electrical overload, cooking oil or gas in the kitchen, storedinflammable liquid, arson, or smoking in bed.

☆ Supported by the Indian Institute of Technology, Kharagpur 721 302,dia, and the Department of Health and Family Welfare, Government ofssam, Guwahati City 6, Assam, India.

☆☆ The author has no conflicts of interest to declare.⁎ Correspondence: Kanchan Chowdhury, PhD, Cryogenic Engineering

entre, Indian Institute of Technology, Kharagpur 721 302, India. Tel.: +91222 283582; +91 94340 10442 (Mobile); fax: +91 3222 282258.E-mail address: chowdhury.kanchan@gmail.com.

ttp://dx.doi.org/10.1016/j.jclinane.2013.12.014952-8180/© 2014 Elsevier Inc. All rights reserved.

sources: 1) inflammable liquids, such as alcohol-containingsolutions (eg, certain prepping solutions) and other volatilechemicals, such as ether or acetone used in the operatingroom (OR), which become even more fire-prone in thepresence of oxygen (O2) and nitrous oxide (N2O); 2) a smallspark or heat that originates in equipment operating near thezone of application of O2 to patients; and 3) in components ofO2 gas lines, liquid O2 tanks, and cylinders that carry pure O2

(near 100%). Metals become readily involved in such fires.As shown in Fig. 1, three elements complete a fire

triangle: 1) fuel, 2) oxidizer, and 3) ignition sources. If one ofthese elements is missing, it is impossible to initiate fire[1,2]. Increasing the intensity of even one of the arms of thistriangle increases the probability of fire. The presence of allthree arms of the fire triangle is a necessary but not sufficientcondition to initiate fire. With the oxidizer, as O2

concentration, pressure, velocity, and temperature increase,the situation becomes more vulnerable to initiation of fire [3].

Fig. 1 Diagram of the three arms of the fire triangle: 1) fuel, 2) oxidizer, and 3) ignition sources.

415Fires in Indian hospitals

As an effective ignition mechanism, a spark needs to possessthe required energy density or the heat generated should besufficient to reach the ignition temperature of the solid, liquid,or gaseous fuel in the given environment, material, andconfiguration. As for fuel, the flammability of materialssubjected to sparks, or the configuration (for solid) ordispersion (for gas) at the spot of application of energy shouldbe such that the heat gained is higher than the heat lost and thetemperature increases to exceed ignition temperature neededfor the prevailing environment. Though accentuation of anyof these three arms of fire triangle increases the chance of fire,it is never guaranteed. An accident is a probabilisticphenomenon that demands that many variables occursimultaneously. Suppression of the intensity of the arms ofthe fire triangle reduces the risk of fire.

2. Literature survey and objective

A hospital generally handles solid materials such as oxygenmasks, nasal cannulae, endotracheal tubes (ETTs) made ofpolyvinyl chloride (PVC) or silicone, dressings, ointments,gowns, beds, blankets, suction catheters, flexible endoscopes,fiberoptic cable coverings, gloves, packaging materials, all ofwhich are prone to fire [4]. However, the hospital uses manychemicals in the OR and pathology laboratory that are highlyflammable in nature. Even gastrointestinal tract gases, rich inmethane, are sometimes highly prone to fire. These chemicalsrender the “fuel” arm unusually strong. Second, O2 gas ismadeavailable in cylinders or pipelines with near 100% purity and isused in the intensive care unit (ICU), neonatal intensive careunit (NICU), and OR routinely. During administration topatients, a substantial amount of O2 gas may leak out,increasing the O2 percentage in the surrounding air. Thissituation strengthens the “oxidizer” arm, increasing the chanceof fire. The “ignition” arm is also present in different forms atall locations within the hospital. For example, electrosurgicalor electrocautery devices, lasers, heated probes, and defibril-

lator pads serve as ignition sources in the OR. As all three armsof the fire triangle are present in the OR environment, it is achallenge to avoid fire at any time in the OR. In the UnitedStates alone, approximately 100 surgical fires are reportedannually. Of this number, 20 cause severe injury, leading toone to two deaths each year [5].

Apart from the fires involvingORbeds, reports in themediaover the last several years have named cigarette, kitchen,storage room, incubator, air conditioner, space heater,ventilator, defibrillator, voltage stabilizer, electrical room,switchboard, electrical box, transformer, motor air handlingunit, X-ray machines, ultrasound machines, and others as thesources of fire. Regulators and valves in O2 cylinders, O2 line,and plastic ETTs carrying near 100% pure O2 have causedmany devastating fires [6,7]. These incidents were analyzed bythe author, who also inspected the possible locations of fire.This review was undertaken to examine the possible rootcauses of such fire incidents that take place in Indian hospitals(particularly in ICUs and NICUs).

3. Methodology

Google searches led to the web links of newspapers andtelevision clips that reported such hospital fire incidents.From these news items, efforts were made to determine thetime, location, and source of each fire. As the keywordsused for the search were in English, it is very likely thatnews items from non-English newspapers did not appear inthe search results.

4. Inclusion and exclusion criteria

Any one particular incident was reviewed from differentnewspapers to determine the time, location, and possiblesource of the fire. If the source of the fire was not found, the

416 K. Chowdhury

report was excluded from this analysis. If a fire occurred in theOR and was the result of flammable vapor from surgicalinstruments and/or O2, it was excluded from the study.However, if an air conditioner, high-voltage source, voltagestabilizer, or robotic instrument was involved in anOR fire, it wasincluded. Any incident reported to have been initiated by arson orany cause not repeated elsewhere in the world, also was excludedfrom this study. If the cause was cigarette smoking, it wasincluded. Observations were based on the reports on hospitalfires across theworld going back over the last several years only.

5. Objective

If a pattern can be established from several fire incidentsand their root cause identified, appropriate remedial actionmay prevent occurrences of similar fire incidents. Somedistinct patterns have been observed in the occurrence offires. The patterns have led to hypotheses that are not newphenomena in industry or commercial or health care sectors;however, those who are involved in medical establishmentsmay not be fully aware of them.

6. Media reports on hospital fires

Tables 1, 2, and 3 provide information on the date, time,location, and source(s) of fire and casualties suffered inincidents involving hospital fires.

Table 1 Hospital fire incidents reported in newspapers, 2004 to 2010

Sl No Year Day Time Country City

1 2004 Aug 30 4:43 PM USA Chicago, IL2 2006 Jan 03 2:00 AM India Hyderabad3 2006 July 06 Midnight USA Dayton, OH4 2007 Mar 07 8:00 AM USA New York, N5 2008 Jan 02 1:30 PM England London6 2008 Jan 23 Early Morning USA Minneapolis7 2008 Mar 13 4:15 AM India Ahmedabad8 2008 Mar 13 2.30 AM India New Delhi9 2008 Nov 16 Night India Meerut, UP10 2009 Jan 10 7:00 AM Philippines Manila11 2009 Jan 31 3:00 AM India Patiala, Punj12 2009 Feb 11 2:00 AM England London

13 2009 May 03 Afternoon India Allahabad14 2010 Feb 02 9:30 AM India Hyderabad15 2010 Feb 03 9:20 AM India Kolkata16 2010 April 15 1:30 AM India Mancherial,17 2010 April 19 2:30 PM India Katni, MP18 2010 May 14 India Nashik, Mah19 2010 June 14 11:30 AM India Siliguri, WB20 2010 Aug 17 Romania Bucharest21 2010 Sep 13 Midnight Pakistan Lahore22 2010 Nov 20 5:20 PM Pakistan Lahore

ICU=intensive care unit, pts=patients.

6.1. Identification of pattern

Four distinct patterns may be observed from reports of thefire incidents described. Most of the fires: 1) occurred inlocations where O2 was being administered to patients, suchas the ICU, NICU, and OR; 2) involved air conditioners andelectrical equipment in the vicinity of O2 application; 3) tookplace on the Indian subcontinent, and 4) the number ofincidents has increased substantially in recent years.

6.2. Hypothesis

Oxygen enrichment of air inside a closed environment,which occurs due to leakage of O2 gas, is responsible for mosthospital fires. Fire may be initiated in any equipment in thevicinity of O2-enriched air if there are ignition sources andeasily ignitable material therein. Occasional sparks (whichare otherwise harmless in ordinary air), heated electrical parts,heated metallic parts due to friction (eg, a bearing), act asignition sources. Lubricating oil, grease, insulation varnish,plastic and other polymers, dust particles, and metals such asaluminium, steel, and other, serve as fuel for fire.

6.3. Analysis

With O2 being administered to a number of patients in anICU simultaneously, leaking of O2 gas through the O2 hoodor mask is not entirely preventable. Without proper

Location of fire Casualties/injuries

Cigarette One deathIncubator One baby deathAir conditioner No injuries

Y Space heater No injuriesAir conditioner No injuries

, MN Incubator One baby burnedIncubator One baby deathIncubator One baby deathIncubator One baby burnedVentilator No injuries

ab Incubator 5 babies burnedElectrical room basement Hundreds

EvacuatedIncubator One baby deathDiesel generator/short circuit One death, 38 injuriesShort circuit in meter box No injuries

AP Incubator One baby deathAir conditioner 8 babies evacuated

arashtra Electrical short circuit in ICU One deathAir conditioner No injuriesAir conditioner 5 baby deathsAir conditioner 3 pt deathsSwitchboard No injuries

Table 2 Hospital fire incidents reported in newspapers, 2011 and 2012

Sl No Year Day Time Country City Location of fire Casualties/injuries

1 2011 Mar 09 Early morning India Beed, Maharashtra Incubator Two baby deaths2 2011 May 27 11:30 AM Bangladesh Chittagong Electrical short circuit in store room No injuries3 2011 June 28 10.30 PM India Chandigarh Ventilator One person injured4 2011 July 24 5:10 AM India Chennai Air conditioner Two pt deaths5 2011 Nov 23 7:24 PM England Bristol O2 cylinder One pt injured6 2011 Dec 09 2:30 AM India Kolkata Air conditioner 93 deaths7 2012 Jan 08 Not known India Hisar, Haryana Electric stabilizer No injuries8 2012 Mar 20 3:00 AM India Jorhat, Assam Radial warmer 26 babies rescued9 2012 Mar 21 9:00 AM India Kolkata Air conditioner No injuries10 2012 Mar 22 8:40 AM India Medinipur, WB Air conditioner No injuries11 2012 April 06 Afternoon India Allahabad Air conditioner No injuries12 2012 April 21 1:00 AM India Guwahati, Assam Air conditioner No injuries13 2012 May 31 3:50 PM India Delhi O2 line 40 pts saved14 2012 June 08 3:15 PM Pakistan Lahore Air conditioner 7 baby deaths15 2012 June 14 5:00AM Australia Adelaide Kitchen No injuries16 2012 July 01 Early morning India Moradabad, UP Air conditioner Two deaths17 2012 July 02 5:00PM India Delhi Air conditioner No injuries18 2012 Aug 17 11:30 AM India Cuttack, Orissa Air conditioner No injuries19 2012 Aug 23 Evening India Mumbai Air conditioner No injuries20 2012 Aug 29 7:50 PM India Delhi Electrical box No injuries21 2012 Sep 05 5:00PM India Jaipur, Rajasthan Air conditioner No injuries22 2012 Sep 06 11:15 PM India Madurai Air conditioner No injuries23 2012 Sep 06 2:19 AM USA Durham, NC Defibrillator One death, three injuries24 2012 Sep 08 8:15 PM India Bokaro, Jharkhand Air conditioner Three deaths25 2012 Sep 25 3:30 PM India Ludhiana, Punjab MCB box (NICU) No injuries26 2012 Sep 25 5:00 PM USA Linton, IN Motor (air handling unit) No injuries27 2012 Oct 02 10:30 PM India Kolkata Air conditioner No injuries28 2012 Oct 23 4:06 AM Taiwan Tainan Storage room 13 deaths, 60 injuries29 2012 Nov 24 10:00 PM India Kolkata Air conditioner No injuries

Pt(s)=patient(s), MCB=microcircuit breaker, NICU=neonatal intensive care unit.

417Fires in Indian hospitals

ventilation, the environment inside the hospital ward mayeasily become rich in O2. As O2 gas is frequently used in theICU, NICU, and OR, these areas are more fire-prone thanother hospital environments. Oxygen gas leaking out fromthe supply room and entering nearby X-ray, magneticresonance imaging (MRI), or ultrasonography rooms alsomay prove hazardous. As reported in manuals from theNational Fire Protection Association USA, the O2 percentageshould not exceed 23.5% in any hospital rooms. Oxygenmonitors are seldom used in hospitals in the Indiansubcontinent to control this parameter.

Oxygen is a colorless, odorless, and tasteless gas. Normalair contains 20.9% of O2 by volume. When the O2

concentration is more than 23.5% by volume, the environmentis known to be O2-rich. Oxygen gas by itself is nonflammablebut it vigorously supports combustion. Many materials, whichare not combustible at all or not easily combustible in normalair, become readily combustible and burn actively in anO2-richatmosphere. The combustion reaction in a material starts whenthe system has some source of ignition energy higher than theminimum ignition energy of the material. A higher O2

concentration lowers the ignition temperature and minimumignition energy requirement of a material. Electrical or metallicsparks or heat provide the ignition energy. The ignition energy

may even come from the chattering of contactors, heatingof lubricants in the bearing, or impact energy of dustparticles. A material that may become just red-hot in airwould give out flame with a higher O2 concentration. Fig. 2shows that, in the presence of O2-rich air, the burning ratesof most plastic material increase substantially. Fig. 3 showsan identical effect in terms of reduction of ignition energyof metal particles in the presence of increased O2

concentration in the air. It essentially means that metalsburn more easily in an O2-rich environment than they do innormal air [6].

However, O2 enrichment of the atmosphere alone may notcause fire. Incorrect design, operation, and maintenance ofO2 systems and use of materials incompatible with O2

service are some of the associated reasons for fire. Fire maystart from an O2 cylinder when rapid release of high-pressureO2 through orifices of the regulators in the presence of dustparticles causes friction or impact resulting in increasedtemperatures, which may be sufficient to ignite the dust. Theignited dust may in turn ignite non-metals, which may bringinner metal components and body within the grip of fire.Oxygen cylinders are responsible for many fires in the ICU.Air conditioners (ACs) have been found to be the startingpoint of many hospital fires in recent times.

Table 3 Hospital fire incidents reported in newspapers: 2013 (up to September)

Sl No Year Day Time Country City Location of fire Casualties/Injuries

1 2013 Jan 01 5:30 PM USA Dayton, OH Transformer No injuries2 2013 Jan 05 2:30 AM India Mangalore, Karnataka Air conditioner No injuries3 2013 Jan 09 10.30 AM India Mangalore Air conditioner No injuries4 2013 Jan 13 3:20 AM India Bikaner, Rajasthan AC and heater 4 infants injured5 2013 Feb 19 9:09 AM Pakistan Karachi Ultrasound laboratory

(basement)Several injuries

6 2013 Feb 20 Not known USA Portland, OR Alcohol-soaked handsanitizer, static electricity

One person injured

7 2013 Feb 23 12 Noon India Kolkata Air conditioner No injuries8 2013 March 6:00 PM Canada Ottawa O2 cylinder One person injured9 2013 Mar 06 7:50 AM Spain Madrid O2 container 3 persons injured10 2013 April 20 4:45 AM Canada Ottawa O2 cylinder 4 persons injured11 2013 April 20 Not known India Ramanathapuram,

TamilnaduAir conditioner No injuries

12 2013 April 21 12 Noon India Allahabad Air conditioner No injuries13 2013 April 26 2 AM Russia Ramensky, near

MoscowElectrical short circuit 38 pt deaths at

psychiatric hospital14 2013 May 01 morning Russia Tambov, Russia Cigarette smoking One pt death15 2013 May 09 morning Russia Krasnodar , Russia Cigarette smoking One pt death16 2013 May 22 6:30 AM Phillipines Davao Electrical overload 195 persons evacuated17 2013 May 23 2 PM India Chromepet, TN Electrical short circuit No injuries18 2013 May 24 5:35 PM Pakistan Lahore Electrical short circuit No loss of life19 2013 May 29 11 AM India New Delhi Air conditioner No injuries20 2013 June 17 Not known India New Delhi Short circuit in AC No injuries.21 2013 June 18 4 AM India Pune Electrical short circuit No injuries. Equipment

burnt.22 2013 June 22 Not known Pakistan Karachi Electrical short circuit No injuries23 2013 July 05 Not known India Sheikhupura, Punjab Electrical fire One injury24 2013 July 26 Not known China Liaoyuan, Jilin Power distribution 39 deaths25 2013 Aug 01 Morning Pakistan Karachi AC machine No injuries26 2013 Aug 05 Evening India Cuttack, Orissa AC machine No injuries27 2013 Aug 22 9 AM Lebanon Beirut Office scanner No injuries28 2013 Aug 25 6-30 PM India New Delhi X-ray unit No injuries29 2013 Sept 13 Pre-dawn Russia Luka, Novgorod Cigarette 37 deaths30 2013 Sept 30 10 AM England Edinburgh Air conditioner No injuries

Pt(s)=patient(s), AC=air conditioner.

418 K. Chowdhury

7. Types of air conditioners

Three types of ACs are generally available: window, split,and central ACs. The window AC is the smallest of the threetypes. It is available in 0.5-TR to 3-TR capacities (1-TR, ortons of refrigeration = 3.5 kW of refrigeration). It is dividedinto two parts: the section that is projected into the room to becooled (ie, evaporator side) and the portion that hangsoutside the room (ie, condenser and compressor side); bothsections are assembled in a single casing. This type of ACmust be installed in a window so that the condenser part isexposed to the outside environment to remove heat. Filter,cooling coil, fan, centrifugal blower, and electrical operatingpanel are all located in the evaporator side. Refrigerant insidethe AC circulates in a closed cycle.

The split AC has two parts: the indoor and outdoorsections. These parts are installed in separate casings and thedistance between them may vary from 5 to 10 meters or even

more. The indoor unit consists of evaporator coil, evaporatorblower with its motor, capillary tube, air filter, electriccontrol, and other parts. This unit is located inside the room,hence the name, indoor unit. It cools the room by suctioningair from the surroundings, cooling it, and returning it backinto the room. It may be wall-mounted or suspended from theceiling. The outdoor unit consists of compressor, condensercoil, and condenser fan with its motor. These two units areconnected with two long pipes: a high-pressure liquid linefrom the condenser and a low-pressure vapor suction line tothe refrigeration compressor. One outdoor unit may be usedto feed up to three indoor units, depending on the load. Asthe compressor is located outside the room, the noise level ina split AC is lower than that of the window AC.

One may observe in Fig. 4 that the indoor unit of the splitAC has been placed just above the patient's bed. As thepatient is administered O2, some O2 may leak out, renderingthe zone O2-rich near the point of application. If an AC

ig. 4 Split air conditioner above the patient's bed in an intensiveare unit. The voltage stabilizer is a potential ignition source.Fig. 2 Burning rate of some plastics versus oxygen concentration.

PMMA = poly(methyl methacrylate), Viton® (fluoroelastomer;DuPont,Wilmington, DE,USA), PTFE = polytetrafluoroethylene [8].

419Fires in Indian hospitals

operates in that zone, it becomes vulnerable to fire. As shownin Fig. 5 and Fig. 6, the motor (to drive the blower) and theelectrical control unit have sufficient potential to generateheat and spark. As the AC is made of plastic materials(particularly as the plastic parts are made thinner to save onweight and price, it is becoming more fire-prone), the spark,oxidizer, and fuel are all ready to set the fire.

Air conditioners use many plastic parts, which arevulnerable to fire in ordinary air and more vulnerable in anO2-rich environment. Though it is safer to use metal, an ACis costlier and heavier and therefore consumes more powerwhen more metals rather than non-metals such as plastics areused. By increasing the use of plastics, the powerconsumption of fans and blowers (AC models are given 3-star, 4-star, and 5-star ratings depending on their powerconsumptions) and capital cost of ACs have been reducedsubstantially. However, the vulnerability of plastics to firehas increased substantially. In the current design andmaterials used in AC construction, plastics may be

Fig. 3 Minimum ignition energy versus oxygen concentration [9].

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unsuitable for use in hospitals, particularly in locations whereO2 gas is administered to patients.

Both split and window ACs have electrical control panelsexposed to the environment of a cold room. A control panelhelps to control AC operation with the help of electronicchips, transformers, and relays. These electrical items oftenproduce sparks, which is usual for their operation. As theseitems are designed to operate in normal air, the sparks do notcause ignition of the materials in normal air. In the presenceof excess O2, these sparks may be the sources of fire.

The motor used to drive the blower in the indoor AC unitis also prone to fire. If the motor bearing becomes jammedand continues to draw current, the resistive part of thewinding will heat up and eventually ignite the plasticssurrounding it.

Electrical wires are often joined with solders, which havelow melting temperatures. Vibrations in the ACs oftenloosen these connections and cause the joints to spark, which

Fig. 5 Indoor unit containing the motor to drive the fan.

Fig. 6 Electrical component and wiring in a split air conditioner(AC) are potential fire sources.

Fig. 8 Split air conditioner (AC) involved in a fire in a pathologylaboratory. The evaporator, the only metal component of the AC, isthe sole part to have survived the fire.

420 K. Chowdhury

may melt the solder joints. Such sparks may be benign inordinary air. However, melting and ignition of the moltensolder occurs at a lower temperature in the presence of higherO2 concentration, increasing the chances of ignition. Forthese reasons, the mandatory use of terminal blocks insteadof solder joints is suggested to avoid sparking.

Central ACs, available in 20 TR to 2000 TR capacities,handlemuch higher refrigeration loads than dowindow or splitAC units. In such a system, the refrigeration plant produceschilled water, which is pumped through the heat exchangercoils located in the air handling unit, and cools the air comingfrom the air-conditioned space (eg, ICU). The system consistsof three parts: the air-conditioned room, air-handling unit, andchilled water plant. The chilled water plant, which is normallylocated outside or on the roof, consists of compressor,condenser, chilled water-air heat exchanger, and pumps. Theblower in the air handling unit draws some fresh air from the

Fig. 7 Inside view of the air handling unit of a central airconditioner.

environment apart from the air coming from the cold room,whichmay already be enriched with O2. The motor driving theblower and the bearing (containing lubricating oil) are exposedto enriched oxygen (Fig. 7). Motor windings and thelubricating oil in the bearing may potentially ignite, as theseare generally hot due to the electric current drawn and friction,respectively. The auto-ignition temperature of the lubricatingoil may decrease in presence of increased O2 concentrations inair and become vulnerable to fire.

Ventilation is an important aspect of hospital manage-ment. The American Society of Heating, Refrigerating andAir Conditioning Engineers (ASHRAE) has publisheddetailed guidelines about ventilation requirements forhospitals and the ways to accomplish these [10–12]. Sincewindow and split ACs have limited ventilation ability (splitACs do not suction fresh air), they cannot prevent build-up ofO2 concentration inside the ward. If hospitals do not havemeans of active ventilation, there will be enrichment of O2

and at other times, O2 deficiency. As the frequency of dooropening decreases in the night, ventilation almost ceases.Usually, O2 concentration would be highest in the vicinity ofthe zone of application and decrease as one moves awayfrom it, due to dispersion and diffusion. So, there is a strongpossibility of an uneven concentration of oxygen in air insidea ward with respect to time and space.

As there is neither any ventilation nor any means ofmixing the air inside the ward, and if O2 gas continues to leakout at the zone of application, O2 concentration maypreferentially and steadily increase in the atmosphere near

ig. 10 Unacceptable cohabitation: air compressor and vacuumystem in the O2 control room.

421Fires in Indian hospitals

the application zone. If any AC operates in the zone of O2

administration, it may lead to fire. For equipment withpotential sources of ignition, local increase in O2 concentra-tion is sufficient to start a fire. A central AC, if designed withcare regarding ventilation, does not allow for increases in O2

concentration. However, ventilation in hospitals may bebetter accomplished by using an enthalpy recovery wheel,which both performs ventilation and saves on the refriger-ation capacity of ACs.

The enthalpy recovery wheel involves transfer of energybetween an exhaust and an inlet airstream through arevolving cylinder filled with air-permeable matrix [13].As the two airstreams pass through the two halves of theenthalpy recovery wheel opposite each other, the wheelrotation facilitates the transfer of energy from the high-temperature airstream to the low-temperature airstreamwithout mixing. Arbitrary direct mixing of fresh air or dooropening destroys the cooling effect of the ACs and oftendoes not ensure sufficient dilution of O2 concentration.

8. Some realities in India

In India, only two percent of households were equippedwith air conditioning as of 2007. But the situation ischanging quickly. McNeil and Letschert [14] estimated thatAC sales in India are growing by about 20% a year. TheBureau of Energy Efficiency, Government of India, Ministryof Power, has set standards for energy efficiency of ACs withsuitable star ratings and encourages consumers to select thelower energy-consuming ACs. One way of reducing powerconsumption is to use lighter construction material, such asplastic, and making it thinner. As a result, vulnerability to fireis bound to increase. Safety guidelines existing in Indianstandards in manufacturing and operation of ACs does notinclude fire safety norms explicitly [15,16].

Fig. 9 Stamp of fire in a pathology laboratory in India.

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There may be sufficient knowledge in Indian hospitalsregarding fires that occur in the OR as a result of anestheticagents. However, effective knowledge of the role played byO2-enriched air or pure O2 in creating fire elsewhere inhospitals may be incomplete. It may be difficult for thehospital staff to identify on their own the exact location ofsources of fire and the causes thereof.

In recent years, the window AC has been largely replacedby the split AC due mainly to the latter's flexibility inallowing for installation anywhere inside the ward. The splitAC ensures that a patient receives maximum comfort as thecooling part (indoor unit) may be placed nearest to thepatient's bed. It is ironic that this very flexibility has provento be its nemesis. This proximity of the AC to a patient (ie,the likely zone of O2 application) renders it greatlyvulnerable to fire in the event that O2 is administered tothe patient and the environment becomes rich in O2.

The split AC is almost entirely composed of plastic exceptfor the evaporator, which is the only part made of metal.After one incident of fire, which occurred in a pathologylaboratory in India, the only part of the AC that survived wasthe evaporator (Fig. 8). In Fig. 9, the burnt AC has beenreplaced by a new unit, though black marks of fire on thewall are still visible. One may note that the O2 (yellow) andN2O (yellow-blue) lines passing through the pathologylaboratory are located below the AC that caught fire.

Many other practices in Indian hospitals are unacceptablefrom a fire hazard point of view. The National Fire ProtectionAssociation USA publications, NFPA 53 [17] and NFPA 99[18], list recommendations, which are not followed in Indianhospitals. In fact, very few of these hospitals in India areaware of the existence of any international codes andstandards for O2 handling. Some of the aberrations are shownin Figs. 10, 11, 12, 13, 14, and 15.

Air compressors and vacuum pumps are located in thesame room as O2 controls (Fig. 10). Leakage of O2 from thecylinders and joints may enrich the air beyond acceptablelevels. As the compressor and vacuum pumps containmotors, bearings, and lubricating oil coming into contactwith O2-enriched air, this situation is very dangerous.

ig. 13 A ceiling fan has many parts that act as a source of fire:enerally unacceptable in the intensive care unit (ICU).

Fig. 11 Unacceptable material: O2 pressure regulator ofaluminium burnt in fire in a hospital.

422 K. Chowdhury

Many parts containing pure O2 are made of aluminium,which is unacceptable practice. Evenwith acceptablematerialssuch as brass, regulators may be ignited, resulting in fires [19].At least one of the hospitals visited by the author had a fire inthe O2 control room; the regulator and pressure gauge wereboth found to be made of aluminium (Figs. 11, 12).

A ceiling fan is no less vulnerable to fire as it containsmotorand mechanical bearings (Fig. 13). These items produce heat.With enriched O2, a fan could well catch fire. As is seen inFig. 4, wall-mounted fans running in ICUs in India are also notacceptable. Electrical wiring is not done professionally,leading to short circuits (Fig. 14). Open coil heaters are used

Fig. 12 Unacceptable material: aluminium casing of O2 pressuregauge burnt in a hospital fire.

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in NICUs to keep the environment warm in winter (Fig. 15).Open red-hot coils, with dust particles deposited on them, maybe a source of fire in an O2-enriched system.

9. Recommendations

9.1 The indoor unit of a split AC or window AC should notbe allowed to be placed near the point of administra-tion of O2. They should be placed at least 4 to 5 metersaway from this point. The farther away they are placedfrom the O2 administration area, the safer they are.However, the cooling effect is then reduced. CentralAC should replace the split and window ACs.

9.2 Split ACs cannot perform any ventilation. Usually awindow AC has a very limited ventilation function.Pumping fresh air from the outside by installing anexhaust fan in reverse (which may send untreated airinside the ward) or through a compressed air pipelinemay be acceptable from the point of view of fire

Fig. 14 Unacceptable electrical wiring in a hospital in India.

Fig. 15 Exposed heater coil is a potential source of fire: anunacceptable item in the intensive care unit.

423Fires in Indian hospitals

prevention. However, the practice increases to a largeextent the refrigeration load of the AC. Using an“enthalpy recovery wheel”, one may achieve ventila-tion while also saving cooled air. However, this optioninvolves a capital investment.

9.3 Heat (transformer, relays, fans, bearings) and spark(relays, loose wires) producing machines, such as O2

concentrator, mechanical ventilator, uninterruptedpower supply, space heaters, ceiling and wall-mountedfans, ordinary tube lights, and electrical switches[including miniature circuit breakers (MCBs)] shouldbe placed at least 4 to 5 meters away from the pointof application of O2. Smoking near the O2 applicationis unacceptable.

9.4 Incubators, radiant heaters, and phototherapy units forneonatal units should be designed in such a way as toprevent O2-enriched air leaking into the chamber thathouses heaters, fans, lights, and chokes, starters, etc.,placed right below or above the infant's bed. Whilethese items are constrained by their proximity to thepoint of application of O2, care should be taken by thedesigners and maintenance people to ensure theirisolation from O2-enriched air to avoid fire. Equipmentused inside the wards are designed to operate safely innormal air. The heat (electrical or friction) or spark(due to routine operation or loose contact) generated ina machine, which otherwise is harmless in normal air,may cause plastics or solder to ignite as O2

concentration in the air increases.9.5 The MRI room, ultrasound room, transformers, main

switches, electrical control panels, X-ray units, andServo Voltage Stabilizers (Purevolt Products (P) Ltd.,New Delhi, India) should be placed away from O2

cylinder storage or the O2 control room. In no wayshould leaked O2 gas migrate to these components.

9.6 The O2 control room preferably should be locatedoutside the hospital building. If it is integral to thehospital building, but has a large exit to the outsidethrough a collapsible gate usually kept unlocked, a smokealarm should be installed and a water supply should bekept to extinguish fire. If the O2 control room is locateddeep inside the building with a narrow exit, an automatic

water sprinkler and smoke alarm should be installed.The cylinder storage or O2 control room should not belocated near a car parking lot or in the basement. It shouldbe at least 4 meters away from a parking area.

9.7 The air compressor room and vacuum room should notbe located near the O2 control room. Housing theserooms together in the same location as the O2 controlroom is unacceptable.

9.8 The outdoor unit of the split AC should not be locatedjust above or very near to the O2 control room, as O2

may be released to create fire in the outdoor unit. Thediesel generator (DG) set should not be located nearthe O2 control room, as unburnt fuel may form anexplosive mixture with O2.

9.9 Oxygen andN2Opipelines should not pass unnecessarilythrough a pathology laboratory. The number of joints inthe O2 and N2O pipelines should be kept to a minimumand should be checked periodically for leakage.

9.10 Color coding of pipelines should be uniform through-out the state (and the country), as per nationalstandards. If coding is improperly followed, it maybe a major cause of accident.

9.11 A low-pressure alarm should be placed outside the O2

control room and after each isolation valve, to be usedfor isolating each hospital ward from the main O2

supply in case of fire.9.12 Some materials are more suitable than others in the O2-

enriched environment. Polytetrafluoroethylene (PTFE;“Teflon”), copper, copper alloys (eg, brass, bronze),nickel, nickel alloys, and thick stainless steel are safermaterials. Most plastics, lubricating oil, soft solders,aluminium, carbon steel, and thin stainless steel areprone to fire in the O2-enriched environment. Allaluminum components in the O2 line should be replacedby brass, bronze, or copper. PTFE is the best material fora seal, but PTFE tape must not be soaked in lubricatingoil. If burnt, PTFE produces toxic fumes.

9.13 All kinds of rusts, dust particles, and powders arepotential sources of fire. Periodic maintenance ofelectrical units should include cleaning of potentialheating spots (or points that are likely to spark) fromdusts. This cleaning should be done specifically toprevent fire as fine dusts are generally considered to bethe biggest culprit in initiating fires (due to theavailability of large surface area per unit mass andlow bulk thermal conductivity).

9.14 Before installation, the O2 pipeline should be thor-oughly cleaned, acid-washed, and alkali-washed,rinsed with hot water, and dried so that it is free ofdust and oil (and grease), which are primarilyresponsible for initiating fire in the O2 control roomand pipelines. The oxygen pipeline generates andaccumulates dust from the system. Oxygen pipelinesand regulator should be cleaned and the non-metalparts replaced by competent professionals at least onceevery two years.

424 K. Chowdhury

9.15 At least one portable O2 monitor (0 - 80%) should beprocured and used by each hospital/nursing home.

9.16 If an O2 cylinder is opened inside, care should be takennot to direct the outlet of O2 gas towards the patient'sbed while opening the regulator. Once O2 starts to bereleased safely, it may be connected to the plasticpipeline. Rarely but sometimes fire erupts and a flamegreater than a meter in length emanates from theregulator while it is being opened, setting fire to thebed and patient in that bed. A decorative skirt is notpermitted to be placed over a cylinder.

9.17 Layout of electrical wirings should be performed byprofessional electricians. Connections made by twist-ing wires and wrapping insulating tapes (use terminalblock connectors instead), haphazard layout, disregardof the color codes for electrical wires, are problems oftraining and attitude of staff, and should be avoided soas to prevent fire.

9.18 An alternative (or emergency) exit door should exist forpatients in each room/ward, which preferably should beaway from the usual exit. It is dangerous to violate thisground rule for a hospital or any public place.

9.19 As O2 cylinders and O2 concentrators increasingly areused at home, recommendations made for hospitalstowards fire prevention are equally applicable at home.Devastating fires have taken place while O2 is used athome.

Acknowledgments

The author is grateful to Mr. Shekhar Manohar Gaikwad,Former M Tech Student, and Mr. Rohan Dutta, FormerResearch Scholar, Cryogenic Engineering Centre, IndianInstitute of Technology, Kharagpur 721 302, India, forhelping in the preparation of the manuscript. The authorwishes to express gratitude to Mr. Tarun Gogoi, ChiefMinister of Assam, and Mr. P.P.Varma, Former ChiefSecretary, Government of Assam, Assam Sachivalaya,Dispur, Guwahati-781006, Assam, India, for facilitatingand supporting visits to many hospitals in the State of Assam.

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