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

What is Silo Gas ?

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

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

Nitrogen Dioxide

Facts and characteristics1. Highly toxic2. Strong bleach like odour3. Low-lying yellow, red or

dark brown fumes in high concentrations

4. Lower concentrations will be colourless

5. Heavier than air….will collect in chutes, feed rooms and the base of a silo

6. Generally begin to reach peak levels about 3 days after the silo has been filled

Nitrogen Dioxide

Facts and characteristics

Cont’d 7. Nitrogen Dioxide will cause severe

irritation to nose and throat. Inflamation of the lungs, shortness of breathe, headaches and nausea will also be present

8. 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

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

Conventional 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

Oxygen Limiting 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

Converted 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

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 structure

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. “Grain Silo Explosion Demo”

2. “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 survived up to 2 hours after being submerged in the grain

Youtube Videos

1. “Stored Products Research and Educational Centre: Grain Bin rescue”

2. “Grain Bin Safety 2011”