Technical Manual - Section 3 (Safety Hazards)

Safety
Automatic or manual shutoff systems at supply headers are
needed for top and bottom loading in the event of leaks or
overfills. Fall protection such as railings are needed for
top-loading racks where employees are exposed to falls.
Drainage and recovery systems may be provided for storm
drainage and to handle spills and leaks. Precautions must be
taken at LPG loading facilities not to overload or
overpressurize tank cars and trucks.
Health
The nature of the health hazards at loading and unloading
facilities depends upon the products being loaded and the
products previously transported in the tank cars, tank trucks,
or marine vessels. Safe work practices and/or appropriate
personal protective equipment may be needed to protect
against hazardous exposures when loading or unloading,
cleaning up spills or leaks, or when gauging, inspecting,
sampling, or performing maintenance activities on loading
facilities or vapor-recovery systems.
TURBINES
Turbines are usually gas- or steam-powered and are typically
used to drive pumps, compressors, blowers, and other refinery
process equipment. Steam enters turbines at high
temperatures and pressures, expands across and drives
rotating blades while directed by fixed blades.
HEALTH AND SAFETY CONSIDERATIONS
Safety
Steam turbines used for exhaust operating under vacuum
should have safety relief valves on the discharge side, both
for protection and to maintain steam in the event of vacuum
failure. Where maximum operating pressure could be greater
than design pressure, steam turbines should be provided with
relief
devices. Consideration should be given to providing
governors and overspeed control devices on turbines.
Health
Safe work practices and/or appropriate personal protective
equipment may be needed for noise, steam and heat
exposures, and during inspection and maintenance activities.
PUMPS, PIPING AND VALVES
Centrifugal and positive-displacement (i.e., reciprocating)
pumps are used to move hydrocarbons, process water, fire
water, and wastewater through piping within the refinery.
Pumps are driven by electric motors, steam turbines, or
internal combustion engines. The pump type, capacity, and
construction materials depend on the service for which it is
used.
Process and utility piping distribute hydrocarbons, steam,
water, and other products throughout the facility. Their size
and construction depend on the type of service, pressure,
temperature, and nature of the products. Vent, drain, and
sample connections are provided on piping, as well as
provisions for blanking.
Different types of valves are used depending on their
operating purpose. These include gate valves, bypass valves,
globe and ball valves, plug valves, block and bleed valves,
and check valves. Valves can be manually or automatically
operated.
HEALTH AND SAFETY CONSIDERATIONS
Fire Protection and Prevention
The potential for fire exists should hydrocarbon pumps,
valves, or lines develop leaks that could allow vapors to reach
sources of ignition. Remote sensors, control valves, fire
valves, and isolation valves should be used to limit the release
of hydrocarbons at pump suction lines in the event of leakage
and /or fire.
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