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Flashlight! Flashlight!
Who's got the flashlight?

By Jeffrey Yago, P.E., CEM


If the standard procedure for turning on your flashlight
includes pounding 10 times on a table top, removing, then
reinserting the same old batteries, and finally staring
blankly into the unlit bulb, then
perhaps it's time to rethink how well you are prepared for
the next power outage or emergency.

after the current rash of wild fires, hurricanes, and power
outages, All of these articles suggest that your emergency
preparedness supplies include a battery-powered flashlight
and extra batteries.
However, there are hundreds of different flashlight types,
using all sizes of batteries. Some have incandescent bulbs,
some have krypton bulbs, some have LED lamps, and some have
fluorescent tubes. In addition, there are flashlights
designed to operate on 6-volt lantern batteries, multiple
AAA, AA, C, or D cell batteries, plug-in rechargeable
batteries, and mechanical motion recharging devices.


Flashlight testing

Five new technology flashlights tested against standard 2
"D" cell flashlights. (Left to right) MagLite, Garrity,
Mini-MagLite, Garrity LED, Dorcy LED, and Eveready 2 "D"
cell flashlight


Ever wonder just how long a flashlight will operate on a set
of batteries? During a real emergency, it is
possible that not only your neighbors, but also everyone in
your entire city or state may be without power. Your
flashlights may be your only source of emergency lighting
for a week or more. Even if
you can find a store that is open, I assure you the
flashlights and batteries were sold out days ago.

You need at least two real emergency flashlights, and expect
to pay up to $20 each, plus another $20 for an extra supply
of good quality batteries and a few extra bulbs.
Rechargeable do not hold
their charge long. Without electricity they cannot be
recharged.

I no longer buy any flashlight that uses the older style
incandescent bulbs and cheap slide switch, as these never
seem to work when you need them and quickly discharge their
batteries. Some use a much brighter krypton bulb. These are
a good choice when you need to shine a spotlight a very long
distance, but they will use up batteries fast.


New flashlight technology
The newest generation use one or more light emitting diodes
(LED) as the light source. Advancements have made a vast
improvement in both their white color quality and
brightness. LED does not have a filament to burn out. LED
lamp has polarized positive (+) and negative (-) terminals.
The theoretical life of an LED lamp is in excess of many
thousands of hours of operation when used with the proper
power source. In addition to long life, an LED lamp greatly
extends how long a given set of batteries will last.


General Electric fluorescent lantern provides room-filling
light
using four "D" cell batteries. Another new lighting is the
fluorescent lantern. Most of these battery-powered lights
look like a
small version of an old camping lantern, not a flashlight.

battery-powered fluorescent light can provide really good
lighting
levels throughout an entire room, and are ideal to
illuminate a
kitchen or living room during evening meals. I recommend
having at least one
battery-powered lantern to go along with any other emergency
flashlights you have, and limit its use to only a few hours
each
evening during a power outage as they consume more power
than any of
the other flashlights we tested.

Unless you want to stock 10 different sizes of batteries, I
suggest
limiting all your battery-powered flashlights, lanterns,
radios, and
electronic games to just two or three basic battery sizes.
This makes
things much simpler when they can get complicated really
fast, and
limiting battery sizes allows stocking more of each. Since
newer
lighting and electronic technology is moving to higher
voltages and
smaller sizes, many of today's battery-powered devices may
require
three or four smaller AA or AAA batteries instead of one or
two of
the larger C or D size batteries typically used in older
devices.


How to select a flashlight
To help demystify the process of buying a flashlight for
real
emergency preparedness, I recently tested five of the most
popular
battery-powered flashlights and lanterns currently being
marketed
against a standard two D cell traditional flashlight. During
a
lengthy power outage, you are primarily interested in
finding your
way around an otherwise dark house, so I have not reviewed
those foot-
long D cell battery-powered flashlights that can shine a
spotlight a
mile away. We want to illuminate a small room, not blind a
deer in
the next county. I would like to point out that this was a
less than
scientific testing process, since we are interested in the
relative
differences between models and not specific individual
performance.
Whatever flaws there were in my testing, it affected all
models the
same.


Testing setup in photography studio shows tripod-mounted
light meter
and measurements of distances for flashlight under test.


Since a flashlight that provides a large or very bright area
of
illumination may have a shorter battery life, I have
included a very
rough measurement of illuminated area along with light
brightness. I
also noted how long the particular flashlight operated on a
single
set of batteries. All flashlight tests started out with the
same
brand of good quality fresh batteries. Note that some
flashlights
require more batteries than other designs, which will also
affect
useful operating life. I am using the term "useful operating
life" to
mean that point at which the light output is no longer
bright enough
to provide an adequate lighting level, not the point when
the light
goes completely out.


Testing procedures
I set up my photography studio with an off-white flat
background that
covered an entire end wall. I took a light level meter that
measures
three different ranges of foot-candle illumination levels
and mounted
it in the center of this background. I then positioned a
stand to
hold each flashlight with the lens exactly six feet from the
light
meter and background. Although I could have achieved
different
readings at other distances, I felt this would be a good
average of
working distance. The measurements of the area being
illuminated were
taken in a totally dark room, with the flashlight under test
being
the only illumination. All of the flashlights produced a
very bright
center area, with a larger outer area that was much less
bright. The
outer areas still had adequate illumination for finding your
way
around a dark room, but only the primary center areas were
bright
enough to read or work by.


Final results
The table summarizes the tests of six flashlights and one
fluorescent
lantern. Although any of these would easily light your way
down a
dark stairwell or rural road, several models provided much
better
lighting quality and longer battery life. All of the
incandescent
flashlights produced a slightly yellow light, while all of
the LED
flashlights and the fluorescent lantern gave off a white
light. The 1-
watt "super bright" LED flashlight I tested by Dorcy was
actually
almost blinding, and provided the largest overall
illumination area.


Measurements being taken in totally dark room of
flashlight's
illuminated circle area. Each flashlight tested had a
totally
different illuminated area even though all were mounted the
same
distance to background.


When reviewing the results of this testing, note the
extremely long
time all of the LED style flashlights lasted, compared to
the
incandescent. In fact, I called it quits after four days of
continuous operation, as both LED flashlights were still
providing
enough light to find your way in a very dark room, but their
light
levels had dropped to a tiny fraction of their original
illumination.
The Garrity white LED was the overall winner in operating
hours, and
did this with only three tiny AAA batteries.

All of the flashlights illuminated a very bright round
circle
directly in the center of focus. However, the fluorescent
lantern was
able to illuminate all areas of my entire 12-foot x 20-foot
studio,
although no areas were illuminated as brightly as a
flashlight. I
strongly recommend owning at least one of these fluorescent
battery
lanterns. I think the traditional slide switch flashlight
with two C
or D cell batteries is not suitable for extended power
outages due to
their shorter operating life and difficulty with their
switches and
battery connections making good electrical contact.

All of the LED style flashlights tested had an anodized
aluminum
housing, a sealed push button switch, and machine-threaded
parts with
waterproof rubber seals. I selected these six "finalists"
due to
their smaller size and rugged construction, and all would
make a good
general purpose flashlight. My hands-down favorite was the
Dorcy "Metal Gear" 1-watt LED model. The Garrity LED was my
second
choice, which actually lasted far longer than the Dorcy LED
model due
to the less bright LED. Both were small with a single LED
lamp, and
both required three small AAA size batteries. I really like
the metal
belt clip on the Dorcy, but some of you may prefer the nylon
pouch
with belt loop that comes with the Garrity.

The 1-watt LED Dorcy "Metal Gear" model produced a very
bright center
area, with a large outer area that was also fairly bright.
The
Garrity LED model produced a large diameter center light
with very
little lighted area outside this circle, which gave the
appearance of
a brightly focused stage spotlight.

Most of the incandescent type flashlights are focused for
much
greater distances than the LED types, but for compact size
and
excellent battery life I believe your emergency flashlights
should be
LED design with a gasketed, moisture-resistant, metal
housing. Most
flashlight manufacturers are starting to add an LED model to
their
product line. I liked the Dorcy 1-watt LED model so much I
purchased
three for myself after the testing ended. Most of the
flashlights in
this article are available from Lowe's, Home Depot, and
Wal-Mart.


Battery considerations
During an extended power outage, you may need to operate a
flashlight
or fluorescent lantern for up to six hours per night, for a
week or
more. This is much longer than most standard flashlights are
intended
to operate, and could consume up to 24 batteries depending
on what
type and size flashlight you purchase. This is still more
batteries
than you normally keep on hand, so you will need to change
your
thinking about stocking extra batteries, and be sure to
check their
expiration dates every few months.

Buying the best flashlight in the world is still a waste of
money if
you are not willing to stock lots of spare high-quality
batteries to
keep it operating. The more expensive alkaline batteries
will last
much longer than standard batteries and are well worth the
cost for
your emergency preparedness. I like to vacuum-pack my
emergency
batteries in multiples of four, for each flashlight's
battery count.
A flashlight requiring three batteries will need several
packs of
twelve batteries per pack. This way you will not need to
open more
sealed packs than necessary at one time, and I keep them
stored with
my emergency flashlights. Do not store batteries in a
freezer as some
people suggest, but you do need to keep them in a cool and
dry
location.

Again, this was a somewhat subjective test, but should still
provide
a good idea of what to look for. Be sure to keep in mind the
area of
illumination when deciding which model is right for you, and
do not
be surprised if you need more than one type to meet all of
your
emergency lighting requirements.