sons. The uses of ammonium nitrate and fuel oil in Oklahoma City, and of jet fuel delivered by commercial airliners at the Pentagon and World Trade Center have escalated the toll from such deadly terrorist attacks.

Terrorist attacks have dominated regions of religious, cultural and political conflict since the latter half of the twentieth century. Sectarian violence in Northern Ireland has resulted in nearly 3000 deaths since 1968, much of them from explosions. Progress in negotiations between Israelis and Palestinians has been hampered by the frequency of terrorist incidents; between 2000 and 2002, Israel sustained two bombings per month. Before they were neutralized in Sri Lanka in 2009, the Liberation Tigers of Tamil Eelam conducted approximately 200 suicide bombings since the late 1980’s. The armed conflicts in Iraq, Afghanistan and Pakistan have all been marked by frequent suicide bombings. Clearly, preparation for any terrorist event in the future must take into account the inevitability of burn injuries as a result of explosive devices [55].

Interventions

A priority in LMIC must be to improve the provision of health care for burns to all in the population so that inequity in acute treatment is eliminated. This includes the training of doctors and nurses in acute burn care management as well as those in the allied services (such as physiotherapists, nutritionists, occupational therapists, psychologists and social workers). However, the reality is that social, political and fiscal challenges make this goal many years distant in the future.

Thus the conclusion to be drawn is that prevention is the key to alleviation of suffering from burns. Truly the best way to treat a burn is to prevent it from happening in the first place. In reality, effective prevention programs will face similar barriers to implementation as those faced by efforts to improve acute care, but in many ways prevention is much more cost-effective, and will clearly reach vastly greater numbers of people. People of LMIC will be best protected from the horrors of burn injuries by expanding the global effort to eliminate burns.

Prevention works. The number of child deaths by injury in OECD nations fell by about 50 % between

1970 and 1995 [218]. According to research in Israel

1998–2000, injury prevention programs were effective in reducing burn-related hospitalizations among infants and toddlers, especially from more affluent communities [168]. In Harstad, Norway, in 1987, a comprehensive community-based injury prevention program characterized by strengthening of public participation and the enhancement of community empowerment achieved by recording and actively using the local burn injury data, resulted in a reduction in burn injuries in children [235].

Aside from the reduction in pain and suffering, prevention efforts are cost-effective as well. It has been estimated that for every dollar spent on smoke alarms, $69 in fire-related costs are saved [147].

The traditional approach to injury prevention involves the three E’s: education, engineering and enforcement. However, although many resources are expended on community education, the beneficial effects are not clear. Two reviews have not identified evidence of beneficial effects from community, school, or clinic based fire safety education on fire injuries [61, 228]. Counseling and educational interventions had only a modest effect on the likelihood of owning a smoke alarm (odds ratio [OR] 1.3) or having a functional alarm (OR = 1.2), but these effects were enhanced in the setting of primary child health care surveillance (OR 1.9 and 1.7, respectively) [61, 62]. Similarly, review of the effectiveness of school education programs in reducing the incidence of burns in Israel noted a lack of efficacy [168].

Engineering (modification of agents or environment) and enforcement (creation and implementation of guidelines, codes and laws) require more resources, but are more effective. There are several examples of successful approaches to reduction of incidence or severity of burns [21].

Smoke detectors

During combustion, the combined hazards of heat and smoke intensify over time to a point at which environmental conditions are incompatible with life. Between the time the fire is discovered and the critical time at which point escape is impossible, is a period during which actions can be taken to minimize or prevent injury. The role of early detection systems is to lengthen this interval. (In some cases, when victims

are overcome by hypoxia and CO poisoning while asleep or intoxicated, there is effectively no interval time period for action.) Data from the United Kingdom, which tracks the interval between the time of ignition and the time of discovery, confirm that smoke alarms result in quicker fire discovery. Sixty-three percent of the home fires in which the alarm was raised by the smoke alarm were discovered within five minutes of ignition, and the fire was confined to the item of origin in 62 % of these incidents [59].

Early detection systems include different types of fire warning equipment such as sprinklers and devices that detect heat or smoke.6 From 1977 to 1982 there was rapid increase in the number of homes protected by smoke alarms, followed by a slower but continual rise in installation through 1993. Although the prevalence of usage has leveled since then, 96 % of homes surveyed by telephone reported having at least one working smoke alarm

6Photoelectric detectors pass a beam a light above a sensor. Under normal conditions, the light beam passes above the sensor with no deflection of light to the sensor, which is positioned at 90 degrees from the light beam. However, when smoke particles in the air cause some of the light to scatter, some of the light is dispersed to the sensor, which then triggers the alarm. Photoelectric alarms respond sooner to fires that begin with a long period of smoldering without flames.

Ionizing detectors contain a small amount of Ameri- cium-241, which emits alpha particles. The Americium ionizes the oxygen and nitrogen in the air of the ionization chamber, causing a small current to flow between the two plates in the chamber. The presence of smoke in the chamber disrupts this current flow, which is then detected and triggers the alarm. Ionizing detectors respond quickly in flaming fires.

Fig. 4. Deaths from fire and burns in the US have declined from a rate of 2.99 per 100,000 in 1981 to 1.2 per 100,000 in 2006, according to the Web-based Injury Statistics Query and Reporting System of the Centers for Disease Control and Prevention (http://webappa.cdc. gov/sasweb/ncipc/mortrate.html). (CDC 2009) Residential fire deaths cause the majority of deaths due to fire and burns in the US, ranging from 70–80 % each year from 1981 through 2006. Age-adjusted death rates from residential fires declined an average of 20 % every five years from 1981 to 1991. The decrease in residential fire death rates recently has been less remarkable, with only a 10 % decrease from 2001 to 2006

[3, 223]. The death rate per 100 reported home structure fires from 2003 to 2006 in the US was twice as high when no working smoke alarm was present (that is, either no smoke alarm was present or an alarm was present but did not operate) compared to the rate with working smoke alarms (1.16 vs. 0.59). Having a working smoke alarm cuts the chances of dying in a residential fire in half [4].

Inversely correlating with the rise in usage of smoke detectors has been the decline in residential fire and flame deaths. The age-adjusted death rate in 1981 from residential fires was 2.28; by 1997 that rate was reduced by almost 50 % (Fig. 4; CDC 2009). Although smoke alarms have contributed significantly to this reduction in mortality, other factors have been beneficial as well, including safer heating and cooking appliances, child resistant lighters, flame resistant mattresses, furniture, and clothing, and improvement in acute care of burn victims.

Many states and the District of Columbia have laws that require smoke alarms to be installed in both new and existing buildings. Other states have laws for specific conditions, such as new home construction, multi-family dwellings, or rental properties. As a result, burn injuries have decreased 26 % and deaths decreased 31 % [149].

These efforts to promote smoke detectors are best combined with accompanying educational efforts so that building occupants develop and rehearse escape plans in advance. Likewise, plans should be made as to whether ancillary devices, such as escape ladders might be necessary [13]. Installing, testing and maintaining smoke alarms are critical for protection from a residential fire, but

they are not enough. A smoke alarm merely sounds the warning, but it cannot by itself remove people from harm. Unfortunately, many households have not developed the escape plans that would allow them to use to best advantage the extra warning time smoke alarms provide. Escape plans will identify obstacles to secondary exits if the main door is blocked, establish a meeting place outside the home for household members to gather, and make provisions for disabled, young or old household members [4].

Almost two-thirds of home fire deaths resulted from fires in properties without sounding smoke alarms. In 2003–2006, smoke alarms were present in roughly two-thirds (69 %) of reported home fires and sounded in roughly half (47 %) of the home fires reported to U. S. fire departments. Forty percent of home fire deaths resulted from fires in which no smoke alarms were present at all. Twenty three percent of the deaths were caused by fires in properties in which smoke alarms were present and but failed to operate [4].

Despite the dissemination of smoke detectors into homes, 2704 people died in 2006 from residential fires [47]. Although the death rate in residential fires is doubled if smoke alarms are either not installed or not functional, the presence of functional alarms does not eliminate the risk of death. Functional smoke alarms were found in 34 % of residential fire deaths from 2000–2004, and the mortality rate in residences with functional smoke alarms was 0.55 per 100,000 [3]. The households with smoke alarms that don’t work now outnumber the households with no alarms by a substantial margin [4]. Any program to ensure adequate protection must include smoke alarm maintenance. In one-fifth of all homes with smoke alarms, none were working [4].

In reality, people do not always evacuate when fire alarms sound. Fire alarms are intended to meet four objectives: 1) warning occupants, 2) stimulating them to respond immediately, 3) initiating the evacuation process, and thus 4) providing enough time to escape. In truth, however, rather than assuming that a fire is occurring, people who hear a fire alarm tend to seek the reason for the alarm, such as the smell of smoke. Once they do recognize a fire, instead of calling the fire department and evacuating, they may engage in other activities such as fighting

the fire or collecting belongings. People often fail to respond for a variety of reasons: 1) sometimes the signal is not recognized as a fire alarm, being misinterpreted as a burglar, elevator, or security door alarm, 2) sometimes people do not know what they should do, particularly if they are outside the home environment such as in a commercial space, 3) because of nuisance alarms, people may not believe the smoke alarm signals a real danger, and 4) because of distance from the alarm, background noise, or individual characteristics, they may not hear the signal [172].

Studies of unwanted alarms have consistently shown that smoke alarms produce far more nuisance activations than real alarms. A study of Veterans Administration hospitals found one unwanted activation for every six devices per year and 15.8 unwanted activations for every real alarm [64]. The 2000 New Zealand smoke alarm installation followup study found that smoke alarms provided warnings of actual fires in 7 % of the households, but 38 % of the households reported problems with nuisance alarms [65].

Regrettably, the stress of nuisance alarms outweighs the benefit of smoke alarm protection to some people. A study in the UK during 1999–2002 conducted group and individual interviews with adults and children to explore perceptions of fire risk, the benefits and problems associated with smoke alarms, and whether they would recommend smoke alarms to others. Some adults described feeling very stressed by false alarms, and expressed resentment about the smoke alarm going off during what was perceived as normal cooking. The perception of some children was that smoke alarms activated any time someone was cooking. As a consequence, smoke alarm activations were not viewed as emergencies. The authors remarked, “In a population already managing a range of health risks, a public health intervention that makes mealtime more, rather than less, stressful, where noise can threaten leisure or relationships with fellow occupants, alarms could pose a threat to immediate wellbeing.” [182]

A Cochrane review of interventions to promote residential smoke alarms and to assess their effect on the prevalence of owned and working smoke alarms and on the incidence of fires and burns was

done of controlled (randomized or non-random- ized) trials published between 1969 and 2007. Of 26 completed trials, 17 were randomized. Counseling and educational interventions, with or without allocation of free or discounted smoke alarms, only modestly increased the likelihood of owning an alarm (OR 1.36) and having an installed, functional alarm (OR 1.29). Only one randomized controlled trial reported injury outcomes, and no effect was found on injuries, hospitalizations or deaths from a smoke alarm donation program. Two trials showed that smoke alarm installation programs increase the likelihood of having a working smoke alarm, and one of these studies also noted a reduction in fire-related injuries. The conclusions of the reviewers were that

(1)programs to promote smoke alarms have only a modest beneficial effect on ownership and function,

(2)programs to promote smoke alarms have no demonstrated beneficial effects on fires or fire-re- lated injuries, (3) community smoke alarm donation programs neither increase smoke alarm prevalence or reduce fires and injuries, and (4) community smoke alarm installation programs increase the prevalence of functional alarms and decrease injuries [62]. There is a paucity of the type of data needed by practitioners and policymakers who are seeking to implement smoke alarm promotion interventions [17].

In 2003–2006, smoke alarms were present but did not sound in 23 % of the home fire deaths (Ahrens). When smoke alarms were not present on all floors of the residence, they sounded in only 4 % of the fires and alerted occupants in only 2 % of the fires (Ahrens). On the other hand, when interconnected smoke alarms are present on all floors, they sounded in half the fires and alerted occupants 26 % of the time (Ahrens). Whereas hardwired alarms operated 91 % of the time, battery-powered alarms sound in only 75 % of fires (Ahrens). Of the alarms that failed to operate, 75 % had missing, disconnected or dead batteries (Ahrens).

In a study in Dallas from 1991–1998, smoke alarms showed no protective efficacy in preventing burn injuries or fire deaths in fires started by arson or by children playing with matches or lighters, although they conferred protection against injuries and deaths from all other causes [105]. In rural North Carolina in 1988, the absence of a smoke alarm was

relatively more lethal in the case of fires in which children were present, and when no one in the house was impaired by alcohol or drug use. Moreover, the presence or absence of a smoke alarm had no correlation with the risk of death when a person with either a cognitive impairment or physical disability was present [190].

In 1998 the Centers for Disease Control and Prevention (CDC), the US Fire Administration, the Consumer Product Safety Commission and several other national organizations combined efforts to develop the Smoke Alarm Installation and Fire Education (SAIFE) Program. The plan includes recruiting local communities and community partners, hiring a local coordinator, canvassing neighborhood homes, installing long-lasting lithium-powered smoke alarms, and providing general fire safety education and 6-month follow-up to determine alarm functionality. This program has demonstrated 90 % functional alarms in follow-up surveys (of those the program installed), potentially saving 610 lives in the 16 states involved [24].

Unfortunately, there are scarce data from LMIC on utilization of smoke alarms. In Mexico, only 9 % of homes in the upper socioeconomic stratum had smoke alarms, and none of the homes in the poorest stratum had alarms. An injury prevention educational campaign that included promotion of smoke alarm installation and use had no effect on the use of smoke alarms. However, this was not surprising, considering that smoke alarms could not be purchased in any of the nearby retail stores [140]. Clearly, more work is needed in LMIC, starting with an analysis of the impact of residential fires on injury and mortality.

An Alaskan study compared photoelectric and ionization smoke alarms in rural Eskimo Inupiat villages and ionization smoke alarms where home area averaged roughly 1,000 square feet or less. At the time of follow-up after installation, 81 % of the ionization homes had working smoke alarms compared to 96 % of the homes with photoelectric devices. Ninety-two percent of the ionization homes but only 11 % of the photoelectric homes had experienced at least one false alarm. Ninety-three percent of the 69 ionization false alarms were due to cooking as were four of the six of the photoelectric false alarms. False alarms were more common in homes that were