Pressure Hazards
Chapter 11
Goetsch
Pressure Hazards
Dangerous condition involving pressure
more than pressurized cylinders
Sources of pressure hazards
Gases trapped in body cavities
Boyle’s law
P1V1 = P2V2, when T is constant
As pressure increases volume decreases
Problem areas
Sinus passages
Middle ear
Lungs
Nitrogen absorption
Decompression sickness
Rapid decrease in pressure
Partial pressure hazards
Hypoxia - reduced available oxygen
Hyperoxia - too much oxygen
Nitrogen narcosis - higher than normal nitrogen pressure
Boilers & pressure vessels
Safety hazards
Design, construction, installation
Poor training of operators
Human error
Mechanical failure
Failure of safety devices
Improper inspections
Improper application of equipment
Insufficient preventive maintenance
Boilers & pressure vessels
Safety hazards
Failure of safety devices
Improper inspections
Improper application of equipment
Insufficient preventive maintenance
Same issues for unfired pressure vessels
Hazards - high pressure systems
Leaks
Pulsation
Vibration
Release of high pressure gases
Whiplash from broken lines
Pressure danger to humans
Anoxia - no oxygen available
Hypoxia - reduced oxygen
Altitude sickness
Hyperoxia - increased concentration of oxygen
Pressure danger to humans
Trapped gas effects in the body
Evolved gas effects - body not able to dissipate absorbed gases fast enough
Dysbarism - formation of gas bubbles in blood and tissue
Creeps, chokes
Measurement of pressure hazards
Sounds - don’t use fingers
Cloth streamers - soap solutions
Scents
Leak detectors
Corrosion
Causes of gas leaks
Contamination by dirt of mechanical joints
Overpressurization
Excessive temperature
Operator errors
Reducing pressure hazards
Proper storage
Training & testing of personnel
Periodic inspections
Proper operating conditions
Relieve pressure from system
Label pressure system - inspection, pressure, flow direction
Reducing pressure hazards
Use appropriate materials
Pressure relief devices
Keep hoses short
Avoid impacts
Secure cylinders
Examine labels