Great Plains NH3 Safety - Manual (Page 39)

2013-07-15 Table of Contents Index 407-551M
Great Plains Manufacturing, Inc. Table of Contents Index 35
Ammonia Maintenance Safety
Over half of NH
3
accidents result from equipment failure.
These accidents can be prevented with responsible
stewardship and maintenance.
With most agricultural equipment, using substandard
parts or deferring maintenance until a part fails, merely
costs needless lost time and money.
With NH
3
equipment,
using unapproved parts,
deferring maintenance, or
operating components past end-of-life,
could cost lives.
Suffocation, Blinding, Burning, Freezing, Disabling and
Disfigurement Hazards:
Do not perform maintenance with anhydrous ammonia in the
system. Fully discharge the system of NH
3
liquid and vapor
before working on the implement. See page 39.
▲ Use only equipment that conforms to applicable
regulations, safety standards and manufacturer
recommendations.
▲ Inspect equipment carefully and thoroughly prior to every
use.
▲ Discharge implement of NH
3
residues before performing
maintenance. Assume any liquid in tubing loops is
extremely hazardous. If not pure NH
3
, it is likely to be
highly concentrated ammonium hydroxide (NH
4
OH).
▲ Maintain equipment as instructed:
Follow all safety guidelines.
Use only approved replacement components.
▲ Replace components as they reach their dated life spans.
Incompatible Cleaners
▲ Unless the implement is free of all ammonia residues, avoid
cleaning the implement with products containing halogen
compounds (most commonly chlorine, such as bleach) or
strong oxidizers (such as any “oxi…” products. NH
3
can
react violently with oxidizers and halogens, and can
produce toxic gases and/or explosive compounds.
Trapped Anhydrous Hazard:
Never service fittings without certain knowledge that the lines
and valves are fully discharged.
Implement systems can trap liquid NH
3
between closed valves,
and inside closed valves (even when the lines on both sides of
the valve are discharged). This NH
3
would then be released,
under pressure, when a fitting is cracked, or a valve opened,
days, weeks, or months after last field operations.
If an unvented ball valve had been closed on a full line, that
liquid would be released under pressure and vaporize in
seconds. It can contain enough liquid NH
3
to render a space
the size of a two-car garage uninhabitable (NH
3
concentration
at IDLH within moments).
If either end of the valve is pointed at or near your face, local
concentration would dramatically higher. The outcome could
be blinding, disfiguring, disabling or fatal.
Incompatible Materials
NH
3
is corrosive to:
aluminum (non-anodized) brass
bronze cadmium
calcium cast iron
copper gold
lithium magnesium
mercury silver
zinc
alloys containing these metals, as well as
galvanized surfaces.
Repairs with incompatible parts are likely to soon result in
malfunctions and a serious accident. Brass parts can fail
rapidly, from the inside out. Compounds formed with other
metals may be unstable or even explosive.