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BY:
Thomas M. Cunningham
U.S. Naval Academy Fire Department
Annapolis, Maryland
For years the fire service in the United States and various support organizations have attempted to spread the message through various public fire education programs that residential smoke detectors that are installed, have working batteries, and are tested monthly increase the possibility of individual(s) lives being saved by at least 50%. These claims are not unfounded, but rather are supported by statistical data collected through the NFIRS (National Fire Incident Reporting System) data collection system. Reports and statistics are put together and distributed by organizations such as the United States Fire Administration (USFA) and the National Fire Protections Association (NFPA).
3) That the public be made aware of nonarousal or arousal dysfunction of children during sleep.
- Abstract
- Table of Contents
- Background
- North Shores F.D
- Fishers F.D
- Arlington TX, F.D
- Los Angeles F.D
- Stow F.D
- NFPA Report
- Research
- Recommendations
- Reference List
The effectiveness of residential smoke detectors can be seen through facts and data collected and analyzed by the United States Fire Administration or the National Fire Protection Agency. But data still shows that two age groups are still the largest loss of life and injury from the effects of fire (FEMA 1997). The two age groups in question that have the highest death rates are children and seniors. The facts concerning children are that they still die at averages higher than that of the general population. Annually 20% of all deaths by fire can be contributed to children having perished in a fire. Children under 1 y ear of age accounted for 2%, ages 1-4 account for approximately 12%, and children 5-9 account for approximately 6%. Estimates state that 2,800 children 14 years old and younger are injured each year by fire and at least 850 are killed in residential structure fires. Of these 70% is under the age of 10 and 40% under the age of five.

Figure 1. Average Percent of Child Fire Injuries and Deaths by Month. Source: NIFRS
There has been a decrease in the number of children’s
deaths over the years. Children age 0-9 years of age have seen decreased data
numbers In 1994 there were 940 deaths accounting for 23%, in 1995-96 these total
deaths went down to 734 and 660 and accounted for 20% and 18 % of the
population. Declines like this in fire deaths can be contributed to the increase
in public fire education and the widespread use of smoke detector alarms in
residential dwellings. The rate of death in preschool children is double what is
the norm for the relative population combined. Studies statistics also show that
young children may also have difficulty escaping burning structures even if a
smoke alarm has been activated (Bruck 1998, Bruck Horasan 1995).
Gender and ethnicity also varies of the rates of
fatalities. Studies have proven that children of African American decent are
more susceptible to death by fire than are white children (Duncan 1999). Winter
months provide for the greatest number of deaths for children (figure #1). This
is consistent with the fact that December and January are the two months that
produce the greatest number of deaths for the general population. Having a
working detector in your home at any time during the year doubles your chances
for survival as shown in fire related data.
North Shore Fire Dept.
The North
Shore Fire Department, under the direction of Lt. Jonathon Cohn, conducted
testing on two volunteer families. Test group one consisted of three males ages
six, eight and 10. Cameras were installed in the bedroom area so that
observations and reaction times could be recorded for accuracy, as well as the
child’s reaction to the nocturnal emergency. Having fallen asleep, fire
department personnel would then come into the home and with the use of non-toxic
smoke generation machines, they would activate the residential fire alarms. The
six-year-old male was awakened first, within a minute he was at his bedroom
window preparing to exit the residence. The 10-year-old male was also awakened
but returned back to sleep. The 10-year-old male was finally awakened after
hearing the six-year-old call for him repeatedly. The eight-year-old was never
alerted until both males verbally called for him. All three males got out in 4.5
minutes. This could have been disastrous if it were a real fire emergency. Fire
research and modeling have concluded that within 4 to 4 ½ minutes a home can
become a raging inferno making escape impossible. Due to this research safety
organizations and officials have concluded that a home evacuation should take no
more than two and a half minutes to execute and complete. The nearest smoke
alarm for North Shore test was located in the hallway outside the boy’s
bedrooms. A second test was conducted utilizing the same three children. In the
second test, the smoke alarm sounded for 10 minutes before the first child woke
up and alerted the others. The reaction times showed an increased deficiency
during the second test.
In test group two, this study utilized five children. During the test, the
14-year-old was the first alerted. But before finally awakening to the activated
alarm, the 14-year-old fell back to sleep twice. The 14-year-old evacuated the
residence after five minutes had elapsed. The four other children were never
awakened by the alarm. During the test the alarm could be heard from outside of
the dwelling by fire department evaluators. All four children were finally
awakened after a parent was sent into the room and awakened them. From the start
of the test to completion total test time was 10 minutes. Interviews conducted
afterward by fire department officials with the children uncovered two startling
facts: (1) that they never heard the activated alarms, and (2) when they did
hear them they did not recognize the sound or what it meant.
A second test was
conducted, and the results showed that within two minutes of activation two of
the children were alerted. This demonstrated a marked improvement in the
reaction time over the results in test session number one. With multiple alarms
sounding, a third child was also alerted. Two of the children were never
awakened after 10 minutes. An activated smoke alarm was then placed within one
foot from the children’s heads. This action resulted in another other child
being alerted. The youngest child who is nine years of age was never alerted to
the danger. This is disturbing because the smoke alarms’ decibel range was
measured at 85 dB; this is equal to that of a lawnmower.
Fishers Fire Dept.
· Getting out of bed and to the floor to avoid the smoke layer over their heads.
· Crawling on hands and knees to the door.
· Feeling door with back of the hand to determine if the door was hot to touch.
· If the door was cool, they were to open slowly and determine if escape through the house is a possibility.
· If the child determined that escape through the house was not possible, they would then go to the bedroom window and attempt an escape through it.
·
Once outside they were to go to the designated meeting place with
the other family members at the predetermined meeting site.
Both test subjects were aware that this would be a test and
that they would need to complete all the objectives to successfully pass the
test. Test subject No.1 was asleep when Chief Lipps began his test. The smoke
machine was started and the smoke detectors activated. The main problem noticed
by evaluators immediately was that the girl was failing to awaken. The fact is
that she did not even stir in her sleep. After a period of time the evaluators
sent her mother into the room to awaken her. When the mother finally succeeded
in awakening the child, she got out of bed and had forgotten everything that the
evaluators had reviewed with her prior to this exercise. She did not crawl,
instead she walked to the door and opened it. She then proceeded downstairs
still groggy from having been awakened abruptly. She then walked into the garage
area. This garage area is where all the gasoline and flammables were stored. She
then stood there dazed and confused instead of proceeding to the designated
meeting area. If this had been a
real fire, test subject No.1 would be another death statistic. Deputy Marshall
Lipps decided that test subject No.1 would be tested again within the month.
Test subject No. 2 passed the exercise on the first
attempt. She completed all the objectives required. Participant No.2 was
immediately alerted by the smoke detector and was awakened, she then performed
the all task required in the allotted time period. The results showed Chief
Lipps that test subject No.1 could possibly be the norm rather than the
exception. Test subject No.2 had practiced the fire escape plan and showed good
retention skills. But the second test on subject No.1 again provided findings
considered to be disturbing to for Captain Lipps.
Test subject No. 1 was revisited again. The smoke alarms
were activated and the girl still was still not awakened by the alarm. The
mother was sent in and on the third time of calling her name she was awakened.
The mother had to verbally shout her name. This time the girl got up and
completed the escape plan by performing all the functions required of her. This
test subject failed on both test by failing to wake up without assistance.
During a real nighttime activation or nocturnal emergency the girl would
now be dead.
The Arlington Fire department in
Texas conducted a similar test to the North Shore and Fishers Fire Department.
Arlington’s test aired on the NBC evening news with Tom Brokaw. Arlington had
also discovered what all the fire industry has never known up until now, and
that is an activated smoke detector alarm will not awaken most children to the
danger of fire in the home.
Arlington Fire Lieutenant Randy Ingram and staff supervised
this drill with the help of volunteer families. The drill and its results were
recorded by NBC5 KXAS in Fort Worth, Texas (11/5/02). Before the evaluation was
to begin evaluators questioned the children concerning how they would perform
when awakened by a smoke detector? The children in this test told evaluators
that they would know what to do in event of a fire in their house. Using smoke
generating machines with non-toxic smoke evaluators began to fill the residence.
Once the drill had begun and the alarms sounded. None of the children were even
awakened or alerted by what was occurring because they were still asleep. One
parent was very disturbed about how their child could sleep through the sound of
an activated smoke alarm.
In every residence that was tested the detectors were
activated for a period of six minutes and the children continued to sleep. Lt.
Ingram stated that he never realized that the children would not awaken to the
sound of smoke alarms, instead evaluators thought that it may take two to three
minutes for the children to be awakened.
This test also clearly demonstrated that these children did
not respond to audible stimuli by the sound that was being generated by the
alarms. They also failed to associate it with imposing danger. One test subject
was awakened when a parent called their name. The child sits up on the bed, the
room has the haze of smoke present and says “what?” In the case with two of
the families in the test, neither activated smoke alarms or shouting of the
children’s names had an effect on their arousal. One parent entered the
sleeping area and attempted to awaken the children by prodding and telling them
that there was a fire that they have to go. The parent then picks up the other
child from the bed and this child continued to remain asleep. The child’s body
resembled that of a bag of potatoes. This parent finally succeeded in alerting
the children but did so after experiencing a certain degree of difficulty.
The children had never heard the alarm but another point of
interest was that they had never practiced their escape exercise with the alarms
going off. Practicing an escape plan with the smoke detectors activated may be
just one part of uncovering this puzzling dilemma that faces the fire industry.
Humans are creatures of habit meaning that we become accustomed to doing things
a certain way and it soon becomes habit.
The families then practiced fire escape planning for two
weeks before another evaluation would take place. The children’s rehearsals
were done with the detectors activated. This was done in order to accustom the
children with the sound of an activated smoke alarm. Lt. Ingram then conducted a
second test. Smoke detectors were activated and the children continued to sleep.
LA County Fire Inspector Mike Brown has now conducted another test
(11/20/02) with the assistance of TV station NBC4 in Los Angeles. The first test
conducted by Insp. Brown used three children, one female, and two males. All
three children were questioned prior to the exercise and the children felt
confident enough that they would know exactly what too do if awakened by a smoke
alarm. Smoke generators were used to activate the alarms and upon activation the
children continued to sleep. The children were awakened only after the parents
moved in to get an arousal response. The next test conducted in LA county used
two males ages 12 and 10. Both boys practiced smoke alarm drills several times a
year and felt confident that they would be alerted by an alarm. During this
drill the 12 year old woke immediately and proceeded to the ten-year-olds room
and alerted him that there was a need to evacuate.
The results seen by these varying fire departments test all
show similar results. That the audible alarms produced by early warning smoke
detectors are not awakening children 5 years of age and older.
The Stow Fire Department originally conducted a study of
approximately 600 children before 1997 to determine if children would sleep
through an activated smoke detector alarm. The results of their initial testing
showed that 70% of the children tested were not awakened. The testing was done
in-home by parents who activated smoke detectors while the children slept and
reported their findings. The Allstate Foundation then awarded the Stow Fire
Department with a grant of $2,000.00 in 1997 to conduct a more thorough study.
The study required the purchasing of 10 detectors and 10 strobe-horn units. The
study was performed on 76 children ages 14 and under. The testing required the
installation of:
In all six tests were performed. Utilizing all the
different signals available greater than 55% of the children failed to be
awakened. The best results came from the use of the horn type signal when placed
inside the children’s sleeping area. The Stow fire department was hoping to
achieve a 95% auditory awakening response rate among the studies participants.
The test showed that two children under the age of five were responsive to the
alarms, while 12 children between the ages of 10 and 14 were alerted during the
test.
Of the participants 11 of 76 were alerted when the detector
was located in the hallway. The numbers increased significantly to 35 children
awakened when detectors are located inside of the sleeping area.
According to the NFPA report on patterns of fire causalities in home
fires by age and sex (Hall, 2001) we can view actual statistics that relate to
children. Between 1994-98, 73% of all fatalities resulting in burns and smoke
inhalation occurred in the home. Death by smoke inhalation accounted for 20% and
death burns resulted in 5%. The national mortality database that maintains death
certificates shows that 73% of fire deaths are due to exposure to byproducts of
combustion. Statistics like this are indicative of the importance of why smoke
detectors should be installed and maintained within residential dwellings.
Detectors offer an early warning system to the occupants that significantly
increase chances of survival in a fire by 50%.
|
Nature
of injury |
Age
6-9 |
Age
10-19 |
|
Burns/smoke
inhalation |
132
(79.0%) |
152
(71.6%) |
|
Smoke
inhalation Only |
32
(19.1%) |
46
(21.7%) |
|
Total |
167 |
213 |
Ref 1. Source: National estimates on NFIRS and NFPA survey
Ref. 1 shows that only three children ages 6-9, and 15
children 10-19 have died from some other cause other than burns and smoke
inhalation. These age groups have very high numbers when compared to other age
groupings that are old enough to save their own lives. The activity that the
victims were involved in has also has an impacted this study. According to the
NFPA figures, this studies statistics show that 41% of all victims were sleeping
at the time of the fire. It also shows that 27.2% were attempting to escape from
the emergency. Combine these figures and 68% of all victims were either asleep
or attempting to escape.
This raises two questions:
Unable to act
accounted for 13.6% of the total. Children ages 10-19 that were attempting to
escape accounted for 29.6% of these averages. For general knowledge concerning
death by fire, children under the age of five are considered to be unable to act
or attempt to escape either due to not having the physical or mental capacity to
do so.
|
Activity |
Age 6-9 |
Age 10-19 |
|
Sleeping |
94
(56.4%) |
103
(48.3%) |
|
Attempting to escape |
47
(28.2%) |
63
(29.6%) |
|
Total |
167 |
213 |
Ref 2. Source: National estimates on NFIRS and NFPA survey
Ref 2 shows a very disturbing figure. Mainly that 56% of
deaths by children 6-9 years old occurred while they were asleep. 48% of 10-19
years of age also show a high number of deaths occurring when sleeping. We know
by use of statistical data that most of these deaths occur in homes were there
are no smoke detection devices or devices that are not operating. What we do not
know is how many of these children slept through alarm activations because
statistical data does not take this into account, thus showing clearly that a
problem as arousal dysfunction exist.
Approximately 40% of all fire deaths occur in homes between
the hours of midnight to 6am. This is at hours when most people are asleep, only
29% occurred between 9pm and midnight and between 6am to 9am. Ref 3 Shows that
the averages between the two age groups. In the 6 to 9 age group, 42 out of 167
death occurred between midnight and 6am, while 86 deaths occurred between 6am
and midnight. In the 10-19 grouping we see a difference. 123 children died
between midnight and 6am, and between 6am and midnight 86 perished. Here we also
see another higher death rate while in the sleep hours.
|
Time of Fire |
Ages 6-9 |
Ages 10-19 |
|
12:01am to 3am |
40 (24.2%) |
63 (29.5%) |
|
3:01am to 6am |
42 (25%) |
60 (28.4%) |
|
Total |
167 |
213 |
Ref 3. National
estimates on NFIRS and NFPA survey
Even though 94% of American homes are equipped with some
sort of early warning smoke detection device (1996) only 42% of fires occurred
in homes without an early warning device. It has been estimated that fire deaths
are 40-50% lower in homes equipped with smoke detectors. In the homes that have
smoke detectors approximately one-third are not operating due to dead or missing
batteries. Statistics clearly show that children are more likely to be sleeping
at the time a fire occurs than are older individuals. A 1994-98 study by the
NFPA shows that out of 577 children ages 6-9, that 261 or 45.2% perished due to
being asleep at the time. 775 out of 2,264 equaling 34.2% of children 10-19 died
while sleeping.
After having conducted preliminary
research into this problem concerning children sleeping through activated fire
and smoke alarms. The facts have uncovered interesting and provocative data to
confirm what these various departments have discovered in every one of their
videotaped test sessions.
A motivated response can be solicited from a known stimulus
during sleep. Grace (1997) looked at the effect of motivational responses to
smoke detector alarms and their waking effectiveness. This study determined that
an individual is able to distinguish between sounds recognizable and
unrecognizable to the participants in the study while they are in the sleep
state. Could signals or sounds produce an emotional response from the
participants? Grace in this study determined that people could distinguish
between sounds and signals while in the sleep state. The use of a persons name
as the stimulus was found to have had the best response averages overall.
Individuals who are sleeping can be prepared to respond to the sound of an
activated smoke alarm. The effectiveness of the stimuli depends upon the
emotional content. This is important when testing concluded that subjects could
be awakened from their sleeping state. Motivational response depends upon the
incentive. Grace (1997) concludes that self-programming can be accomplished by
the individuals to awaken to certain types of stimulus to a certain extent.
A report (Busby & Pivik, 1983) on “Failure of high
intensity auditory stimuli to affect behavioral arousal in children during the
first sleep cycle.” This study examined children 8-12 years of age. This
research attempted to determine children’s arousal to auditory stimuli
occurring during the first cycle of sleep to further understand both
physiological and behavior indices. The test sessions were conducted to study
the effects on hyperactive children using non-hyperactive controls. During this
testing researchers used 123 dB sounds (pressure level of 0.0002 dynes/cm2) and
obtained no auditory response or sustained awakenings. Researchers conducting
the study consider this to be 90 dB above normal waking threshold values. 50% of
stage 2 and 25% of stage 4 sleep produced partial response or momentary
physiologic arousal in the children. Any arousal that occurred
was short-lived in duration and the participants immediately returned to the
Sleep state. With continuing or increased auditory stimulus intensity there was
still no response.
A second study (Busby & Pivik, 1985) “Auditory
arousal thresholds during sleep in hyperkinectic children” also produced
results similar to those divulged in Busby & Piviks first report. Hyperkinetic
is defined as a “general
restlessness” or “excessive movement”
such as those characterizing children with attention
deficit disorder (ADD) or hyperkinesis.
Arousal
thresholds have usually been determined through the use of auditory stimuli with
various criteria to determine arousal state. The criteria (Bonnet MH,
Johnson L.C 1978) for subawakening indications
including those considered being physiological and confirmed by specific
behavioral responses (Price LJ, Kremen I.
1980). Studies (Zimmerman WB
1970) have indicated that intensity of stimulus, sleep stage, and time of night
produce variables that are important determinates in the arousal process (Keefe
FB, Johnson L.C., Hunter EJ 1971). Busby & Pivik attempted
to determine the auditory response in “hyperkinetic” children to auditory
stimuli during various sleep cycles. Researchers were attempting to find
evidence of sleep related arousal dysfunctions. Researchers attempted to prove
that children suffering from ADD (attention deficit disorder) have associated
symptoms that include impulsiveness, deficits in attention, motor control, and
arousal dysfunction. When conducting this study, researchers used three control
groups that included medicated hyperkinetic children (MHK), non-medicated
hyperkinetic (NHK) children, and control children. The control group were
evaluated and cleared as not experiencing hyperkinetic symptoms and who were not
on any type of medication.
The study also provides startling results. Researchers found a behavioral
response inability in all three-study groups to be aroused by intense audible
signals up to 123 dB. They were also astonished that the group that had the most
responses was the NHK group. Twenty-four preadolescent (8-12 years old) male
subjects participated in this study. The participants would be subjected to
auditory stimuli for durations of 3 seconds on, 3 seconds off. The auditory
stimulus was delivered through the use of earphone inserts. To produce a
response from the participants, signal delivery would be intensified by
increments of 2-5 dB. These signals would be delivered starting within the
waking threshold values determined for children. The study showed children
experienced arousal dysfunction at intensities up to 123 dB. This is 90-100 dB
above the normal waking threshold levels.
A non-response by the participants occurred in 227 out of
432 attempts, this equals a 52.5% failure rate. 13% of the participants had
non-sustained physiological arousals, these were short in duration and in all
cases the participants returned to their sleep state even with continued and
increasing auditory stimulus. Responses were produced from the participants
either vocally or by the participant pressing a button to acknowledge that they
were aroused. These arousals occurred in 148 out of 432 attempts, equaling a
65.7% failure ratio. The study did show that arousals from REM sleep exceeded
those of stage 2 sleep.
The control (normal) children while in SWS (slow wave
sleep) had no response to 23 attempts over 100 dB. In stage 2 sleep 28 out of 89
(31.5%) responded at 111.1 dB. In REM sleep there was 26 out of 47 (55.3%) at
107.5 dB. The total arousal/attempts for the control children resulted in 54/159
or a 34% response rate.
The results of this study suggest that the intensity to elicit arousals among children are much smaller and higher than comparable values found in research studies involving adults. Researchers believe that this is due to the absence of cortical or behavioral arousal associated with parasomnias such as sleepwalking, sleep talking, or enuresis (bedwetting). What was also noted in this study is that it was virtually impossible to gain a positive response during the first cycle of sleep. There was also a noticeable diminution in overall arousals demonstrated throughout the night by the participants.
Researchers have concluded that a dysfunction related to
“waking underarousal,” which will assuage the increase of sensitivity to
auditory stimulation normally associated with sleep.
Another report, (Duncan.1999) from the University of
Canterbury in Christ Church New Zealand gives interesting insight to the current
phenomenon that has been uncovered concerning underarousal in children. “The
Effectiveness of the Domestic Smoke Alarm Signal” was released in March of
1999. This study was conducted to determine the response times to alarm
activations and to determine what age groups were at the greatest risk from the
effects of fire. The focus of the study was to examine whether inexpensive smoke
detector alarms could perform their function, and to what degree of
effectiveness the early warning signal alerted the occupants in residential
dwellings. The study also provided recommendations on minimizing risk to
occupants.
New Zealand fire fatality statistics show that the highest
number of fatalities occur to 20-29 year olds, and “children” under the age
of nine. The study revealed that children under the age of nine experience the
deepest sleep of all the age groups that were studied. That the time actually
spent in deep sleep (stage 3 sleep) shows to be the most detrimental to a child
being alerted by an activated smoke detector alarm.
Twenty juniors from six to 17 years of age participated.
The results showed that 85% of these participants slept through one or both of
the alarm activations. The study also showed data that adults exposed to the
same stimulus were awakened by the alarm signal 100% of the time. To give
validity to the study, smoke detectors were activated between the times of
2am-6am. This was determined by utilizing fire data that showed that these were
the hours when most fire related fatalities occur within a residential
structure.
The study performed 229 individual exposures to activated
smoke alarm event. 26 participants (74%)
reported not being alerted by the smoke alarm, and 18 (69%) cases were children
under the age of ten. Studies show that children ten years of age and under may
need a stronger stimulus to be alerted when sleeping. Eight of the studies
participants were under the age of ten (from 1 to 9 years of age) and of equal
sexes (4 males and 4 females). All participants were exposed to at least one
alarm activation. The decibels in the children’s rooms were measured as being
75dBA when doors were left open. With the doors closed the audible sound was
measured at 67dBA. These dBA ranges were not significantly different from what
was measured in the parent’s bedrooms.
This decibel range was enough to cause arousal in the
adults. This test resulted in only one child (age 9) wakened by the alarm
activation. The result of this study shows that 87.5% of the junior participants
failed to be aroused when exposed to two smoke detector activations. The study
shows conclusive evidence that children cannot be reliably awakened by
the signal generated by a domestic smoke alarm within a residential structure.
If an activated smoke alarms sounds at night this study suggest that children
will not be alerted and will not respond accordingly.
A case study showed that a 3 year old male child exposed to
5 activations by an alarm measured at 65dBA (detector in hallway) and 91dBA
(detector inside of bedroom) failed to be alerted by the smoke alarm activation.
The location of the detectors failed to give a positive result in this case
study.
The study concluded that:
· Test alarms were generally terminated in less than thirty seconds.
The Fire Code Reform Research Program (March, 1998)
released a study on sleep arousal in children and adults from smoke detectors.
Another study was conducted at Victoria University in Melbourne Australia were
Professor Dorothy Bruck is on staff at Victoria’s Department of Psychology.
The study gives insight into the ineffectiveness of inexpensive residential
smoke alarms when attempting to arouse children from sleep.
The focus of this study was on whether children could be
awakened to smoke detector activations at 60 dBA when the detector is located in
a hallway and the bedroom door is left open. At the time of this study this was
the standard location placement of smoke detectors that was being advocated by
fire organizations. Another study (Nober, et al 1981) used adult participants.
The Nober study showed that adults could respond within 21 seconds to a smoke
detection alarm activation during sleep.
Participants in this study were between 18 to 24 years of age. They failed to be awakened 30% of the time after exposure to a 60dBA smoke detector alarm (Bruck, D., Horasan, M.1995). This is consistent with studies that show children and young adults experience longer deep sleep (slow wave sleep) periods than adults and seniors. Prior to this there had been no studies performed concerning children’s arousal performance to smoke detector activations.
What is also noted in this study is the fact that in newer homes we also see a significant change in design. The change occurred in the distance between the sleeping areas of residential structures. Distances between children’s and adults sleeping areas have grown distant when compared to that found in older structures. In event of a fire this may add to a minor delay in alerting or rescuing children if they fail to awaken from their sleep state independently.
For this study 20 junior participants were recruited and
used. The ages of the participants ranged from 6-17 years. There were 9 males
and 11 females for an average mean of 11.6 years.
All test subjects were screened for problem factors such as
hearing, sleep patterns, illness, etc. All were found to be healthy and within
the parameters predetermined as acceptable by the evaluators. Participants were
also required to undergo other testing to determine suitability for
participation. All alarms activations would occur between the time of 1:00AM and
4:30AM.
Testing was conducted and the results showed that there
existed a noticeable problem among the younger participants. In the junior age
group (6-17 years) 69.3% or 2/3 of the group slept through the three-minute
activation period. This average was determined over a two-night period.
Three of the twenty children in the test were awakened by
the alarms on both nights leading to results that showed the unreliability of
smoke detectors to awaken children. Six children were awakened during one night
of testing, but all other eleven participants slept through the smoke detector
activations on both nights. The studies final results showed that 85% of the
junior participants failed the test when audible alarms at 60 dB were used. The
16 and 17-year-old participants were alerted on both nights of the test.
Another published study (Bruck, 1999) examined
non-awakening in children in response to a smoke detector alarm. This study was
published in the Fire Safety Journal no.32. The study was conducted in response
to the need for further research on children’s non-arousal to activated smoke
detectors as loud as 60 dB. The testing would occur at approximately midpoint
during the households sleep period. The time coincided with the documented times
when the greatest number of fire fatalities occur within residential dwellings.
The time chosen was between midnight and 6 am. The study utilized 20 child
participants between the ages of 6-17 years of age. In this group there were 9
males and 11 females with a mean average age of 11.6 years.
The study concluded with the findings that children would
not reliably awaken to a smoke detector that was located in a hallway. 85% of
the participants failed to awaken on either night of the test. This shows a
definite need for detectors to be located within the sleeping area as well.
These results were received during the middle third of the
children’s sleep period. This period was selected because the greatest degree
when non-responsiveness would occur during the first third of a child’s sleep
period. Measurements were taken prior to testing to ensure that all participants
received a 60 dB signal at pillow level + or – 3 dB. This study gives
creditability to the fact that severe implications to children can arise from a
nocturnal fire emergency.
Researchers noted that due to the amount of deep sleep that
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