WELLINGTON COUNTY
SILO GAS AND HAZARD AWARNESS
Learning Outcomes
The participant will:
 Discuss gases formed in farm silos
 Discuss hazards and characteristics of Carbon
Dioxide and Nitrogen Dioxide
 Identify common types of silos
 Discuss safety hazards and procedures for silo
emergencies
silo gas is formed
within the confined
space of a silo after
chopped sileage is
loaded into the silo
Natural fermentation
takes place, releasing
gases including
carbon dioxide and
nitrogen dioxide
What is Silo
Gas ?
Carbon
Dioxide
Facts and characteristics
1.
This gas is produced
within a silo in high
amounts
2.
CO2 displaces
oxygen inside the silo
3.
Odourless and
colourless
4.
CO2 is heavier than
air and will settle in
low-lying areas
5.
High concentrations
of CO2 give little
warning to persons
about to be overcome
by lack of oxygen
Facts and characteristics
1.
2.
3.
4.
5.
6.
Highly toxic
Strong bleach like odour
Low-lying yellow, red or
dark brown fumes in high
concentrations
Lower concentrations will
be colourless
Heavier than air….will
collect in chutes, feed
rooms and the base of a
silo
Generally begin to reach
peak levels about 3 days
after the silo has been filled
Nitrogen
Dioxide
Facts and characteristics
Cont’d
7.
8.
Nitrogen Dioxide will cause severe
irritation to nose and throat.
Inflamation of the lungs, shortness
of breathe, headaches and nausea
will also be present
Symptoms may present themselves
similar to phnemonia 2 to 6 weeks
after exposure
What makes this gas especially
dangerous is that a low-level
exposure may be accompanied by
minor discomfort and little or no
pain. Death has occurred hours later
as fluid collects in the lungs.
Emergency responders have died in
their sleep after an exposure
Nitrogen
Dioxide
Youtube Videos

1. “Silo Gas Concerns”

2. “Deadly Silo Gas Video”
Common Types of Silos
1.
Conventional Silos
2.
Oxygen Limiting Silos
3.
Converted oxygen Limiting Silos

Made of banded concrete
slabs, poured concrete or
steel plates

Top un-loading

Fires may occur from
malfunctioning unloading
equip, spontaneous
combustion, crops put away
too dry or barn fires in close
proximity to the silo

Rescue may be required if
workers enter the silo to
service unloading equipment
Conventional
Silos

Made of poured concrete or
steel plates

Unloaded from the bottom

Fires usually occur from
oxygen leaking into the silo
through seams, unloading
areas, crops put in too dry,
barn fires in close proximity

Workers generally do not
have to enter this type of silo
during unloading phase

Extremely O2 deficient
atmosphere
Oxygen Limiting
Silos

An oxygen limiting silo that
has been converted to a
conventional silo

May be unloaded from the
top or bottom

Hazards from both styles of
silo may be present
Converted Oxygen
Limiting Silos
Safety Hazards and
Procedures
FIRES





Toxic gases may be
produced when a silo is
burning
Grain dust may produce
explosive atmospheres
Never enter a burning silo
Ensure adequate water
supply before attempting
to suppress the fire
Consider the use of foam
Safety Hazards and
Procedures
FIRES

In “conventional silo’s”
only apply as much water
as necessary to ensure
containment

Large amounts of water
will collapse the structure

Must empty the structure
to ensure extinguishment

Do not climb outside
ladder…heat may have
weakened the ladder or
Safety Hazards and
Procedures
FIRES



In “oxygen limiting silos”
never open hatches, doors
or spray water into the
structure
Introducing water and
oxygen may result in an
explosion
Specific manufacturer
should be consulted for
suppression procedures
Youtube Videos
1.
2.
“Grain Silo Explosion Demo”
“Live Dust Explosion at FM Research
Centre”
Safety Hazards and
Procedures
RESCUES






Identify all risks
Use air monitors to
determine O2 deficient
atmospheres
May require the use of
mechanical ventilation
Lock-out and tag-out any
power sources including
loading and un-loading
equip
Use of SCBA and
harness’s will be required
Treat as a confined space
and follow SOG’s and
dept. protocols
Safety Hazards and
Procedures
Grain Entrapment








Full ppe including harness and life
line shall be worn by rescuer
Ensure all power is locked and
tagged out
If worker is submerged or cannot
be pulled out cut “V” or “U” shaped
holes in the side of the silo on
opposite sides and equally around
DO NOT open the hopper or hole
beneath the victim
Use retaining walls or “coffer dam”
if grain is above victims head
Use shovels and vacuums to
remove grain from around the
victim
Provide breathing assistance if
required
DON’T GIVE UP…persons have
Youtube Videos
1.
“Stored Products Research and Educational
Centre: Grain Bin rescue”
2.
“Grain Bin Safety 2011”