What Is The Health and Environmental
Care Procedure For Transformer Oils?
Health issues
Users should obtain a Material Safety
Data Sheet (MSDS) for each dielectric fluid in use. Where
instructions differ from recommendations made here, the instructions
of the manufacturer are to be followed.
Although there is no special risk
involved in the normal handling of insulating fluids addressed in
this guide, attention should be focused to the general need for
personal hygiene or the practice of washing skin and clothing that
may have come in contact with insulating oil. Personnel should avoid
contact of the fluid with their eyes.
When dielectric liquids have to be
disposed of, certain precautions are necessary to comply with local,
state, and federal requirements in the United States. These oils are
generally classified as special, regulated or hazardous waste
depending upon the individual state.
The following procedures are not
intended to supersede local, state, or federal regulations. Unless a
PCB analysis has been performed, it is prudent to assume that the
batch of oil contains PCBs and to act accordingly. The absence of
PCBs in a volume of oil in or from a piece of equipment can be
established only by analysis of that oil.
Leaks and spills
During equipment inspection
or servicing, routine checks should be made of the equipment and
surroundings for leaks. Areas to check and repair should include
valves, bushings, gauges, tap changers, welds, sample ports, manhole
covers, pipe fittings, pressure relief valves, etc. The user is
referred to IEEE Std 980-1994.
New transformer oil as
received from a refiner is very unlikely to contain PCBs. However,
many older transformers and other pieces of electrical equipment in
service are filled with mineral insulating oil that contains PCBs.
Since 1977, various federal,
state, and local environmental regulations have governed the handling
and processing of mineral oils containing PCBs. While these
regulations can add substantially to the complexity of spill cleanup
and disposal of oils, they should not be disregarded.
Minor spills
Minor spills, such as those
occurring in the manufacture or repair of equipment, can be cleaned
using absorbent rags or other materials.
Spills on soil
Soil acts as an absorbent
and should not be allowed to become saturated with mineral insulating
oil. Users should consult the applicable local, state, and federal
guidelines in the United States for spills of mineral oil onto soil
and the remedies available. Depending on state and local regulations,
spills to soil may have to be reported to one or more regulatory
agencies.
Spills on water
Because mineral insulating
oils float on water, a spill can be contained by using floating booms
or dikes. Section 311 of the Federal Water Pollution Control Act as
amended, 33 U.S.C. 1251 et seq, also known as the Clean Water Act as
found in Title 40 Code of Federal Regulations Part 110, imposes
reporting requirements for petroleum oils that are spilled into
navigable water ways.
The requirement to report is
triggered by the appearance of a sheen on the surface of the water.
If a sheen is noted, the U. S. Coast Guard must be notified, as well
as the National Response Center.
Once the mineral oil has
been concentrated, it can be removed from the surface of the water by
systems that are normally used for petroleum spills. These include
pumps, skimmers, physical absorbents, and fibers that are fabricated
into floating ropes.
NOTE—If spilled mineral
insulating oils are known or assumed to contain any concentration of
PCBs, they must be treated as a PCB containing liquid. Also refer to
the Spill Policy Guide of the Environmental Protection Agency (see
PCBs 761.120, Title 40 Code of Federal Regulations Part 761).
