In the beginning only the
Immortals had Fire. Prometheus looked
with compassion on the cheerless creatures of earth. In defiance of the gods he stole Fire from the heavens and
brought it to earth.
Yesterday was the first day
of summer in the Northern Hemisphere. Although, it has felt as if summer
has been with us for several weeks. Across the country temperatures have
soared, creating new weather records. Living in the southwest we are no
strangers to summer heat and drought. The combination all too often
results in disastrous wildfires.
Throughout history
firefighters have been the heroes who braved the flames of Prometheus to
protect the towns and homes of the citizenry.
Because of the dangerous conditions they faced, firefighters were given
special protective clothing which differentiated them from the populace. One of the most familiar apparel was worn
from the earliest times by Japanese Firemen.
Their jackets (Hanten) were made of various materials. In the Edo period some were made from deerskin.
In the 19th C they were constructed from quilted wool or cotton,
sometimes with silk linings. The unique
feature of these jackets, from an artistic point of view, was the elaborate
decorations (many were considered lucky or protective symbols) which were
woven, painted or embroidered on the surface of the garment, as well as on
chest protectors (Maekeke). There are
many examples of these vintage fire jackets to be seen on the internet.
One component of many
protective garments has been used for centuries. It is the mineral asbestos.
Asbestos is found throughout the world and its fibers were used as reinforcement in early pottery. Once the
fire resistant properties of asbestos were known the fibers were woven into
cloth. The unfortunate aspect to the
use of this mineral in a wide variety of applications, is the fact that
asbestos fibers are carcinogenic and could cause Mesotheliosis. Over 50 countries have banned the use of
asbestos fibers, the US is not one of them.
Modern firefighters wear garments
called “turnouts”, protective clothing.
These garments have 3 layers: an outer shell, a moisture barrier and a
thermal barrier with pockets of air (dead zone) in between the layers. Footwear is boots with a steel toe
insert or rubber boots. There are additional items such
as gloves, helmets and hoods. Depending
upon the type of fire, they may also wear hazmat suits. For fighting wild fires their clothing is modified. Their garments are a single layer, they wear industrial hard hats and leather logging boots. They cannot wear steel-toed boots nor rubber boots due to the heat conditions of the fire.
These garments are made of a
combination of two fibers of the nylon family : Nomex and Kevlar. Both of these synthetics are product of the
DuPont Corporation and are variants of aramid. Kevlar is an aramid that does not melt, is highly flame
resistant, is exceptionally strong (5 times stronger than steel on a weight
basis). It has a high resistance to stretch and maintains its shape and form at
high temperatures. It was first synthesized in 1971.
Nomex is a variant of aramid but unlike Kevlar,
Nomex cannot align during filament formation and therefore has poor
strength. However it also has excellent
thermal, chemical and radiation resistance.
Nonex was developed in the early 1960’s and first marketed in 1967.May the Immortals protect them all.
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