Great Plains NH3 Safety - Manual (Page 9)

Great Plains Manufacturing, Inc. Table of Contents Index Anhydrous Ammonia Information 5
2013-07-15 Table of Contents Index 407-551M
Why Anhydrous Ammonia (NH
3
)
Differs…
…from typical liquid fertilizers:
▲ NH
3
is intensely hygroscopic:
▲ NH
3
is highly caustic:
▲ NH
3
is volatile:
▲ NH
3
has a high heat of vaporization:
▲ NH
3
is combustible:
▲ NH
3
is reactive:
▲ NH
3
is attractive to criminals:
On contact with water, such as unprotected skin, eyes,
mouth, airway and lungs, it dissolves immediately,
desiccating the cells and forming ammonium hydroxide.
Ammonium hydroxide formed on contact is a strongly
corrosive alkaline solution, resulting in severe chemical
burning of skin and mucous membranes.
NH
3
boils at -28
°F (-33.4 °C), expanding by over 850 times.
It remains liquid in the nurse tank only because it is
pressurized at up to 250 psi. Leaks or above-ground releases
immediately cause an expanding gas cloud. Tanks begin
venting above 116
°F (46.7 °C).
NH
3
is a powerful refrigerant. Evaporating (boiling) liquid
NH
3
may be at -100
°F (-73 °C), freezing whatever water it
touches (in addition to the other hazards). This can freeze
clothing to skin, prolonging tissue damage.
Although NH
3
generally does not burn with a self-sustaining
flame in the field, it is a significant fire hazard in closed areas
and/or if released near hot ignition sources (such as during
welding on implements).
Although the reactivity is classified as “0” (in the NFPA
3-1-0 diamond for emergency response purposes), NH
3
does
react with various materials, and can produce hazardous by-
products and/or have hazardous side-effects.
NH
3
is corrosive to a surprising number of metals (see
page 35). Repairs with incompatible parts are likely to result
in malfunctions and a serious accident. Brass parts in
particular can fail rapidly, from the inside out.
Mixing NH
3
with some common household and agricultural
chemicals can, for example, produce highly toxic gas. Never
mix NH
3
with acids.
Do not leave a loaded tank unattended. Secure your tank.
Clandestine lab operators steal NH
3
from unattended nurse
tanks. Criminals and vandals often leave a tank in an unsafe
state.
0
FR
OSTBITE
FR
OSTBITE
CORROSIVE