Property Damage (Fire / Explosion) – While performing Hot Work in an Excavation
Creating an ignition source (flame, heat, sparks, non-intrinsically safe equipment, molten metal or direct flames) in a combustible atmosphere (flammable materials/vapors) leading to fire or explosion.
Impinging heat to surrounding process equipment, causing possible thermal expansion resulting in the release of hydrocarbons,
Arc from welding, possibly setting off fire detection / mitigation systems (i.e., deluge systems, alarms resulting in possible unit shut downs, etc.)
Interference with other simultaneous work in close proximity (e.g., work involving breaking containment and potential release of combustible gases while hot work is present.)
Hazards associated with welding equipment:
Damage and defective parts, if not replaced prior to start of the job
If oxy-acetylene cylinders do not have sufficient material in the cylinders prior to start of the job, backflow can happen if one cylinder goes empty during operation which can cause:
A system pressure imbalance.
Mixing of oxy and fuel inside the hose.
Flashback caused by reverse flow of gas through the torch and back through to the hose, regulator and/or cylinder, potentially causing an explosion
Fire or explosion caused by ignition of flammable/combustible vapors/materials present in the excavation.
Personal Injury (Safety / Human Health)
Excavation cave-ins leading to entrapment and potential suffocation.
Falling into excavations leading to injury of death.