E36 TECHNICAL BULLETIN #2: 5/2/94
Relationship of Potassium Acetate Runway Deicer to Airport Lighting Cables

Following is a summary of a report to the General Session of the 28th International Aviation Snow Symposium in Buffalo, NY, on April 26th, 1994, by Keith Johnson, General Manager of Cryotech Deicing Technology.

SUMMARY
Potassium acetate runway deicers ("the Deicer") were introduced in Europe in 1988. Today, the Deicer is being used by over 200 major airports and military bases worldwide. Since introduction six years ago, there have been two reported cases (one in Europe) of increased failure rates of runway lighting circuits associated with the use of the Deicer. In both cases, the failures have been attributed to older cables in poor condition contaminated with the Deicer, which has a low resistance to electricity.

JFK INCIDENT
In January 1994, Cryotech received word that runway lighting circuits were failing at New York's JFK Airport. A tie to heavy use of Cryotech's potassium acetate deicer (E36) was suspected. Failures occurred on lighting circuits with a history of problems due to age and water in electrical components. The circuits had for some time been under a program of repair. Circuits in good condition were unaffected.

While an investigation was underway to determine the cause, Cryotech issued an industry-wide bulletin advising airports of the incident and the fact that the Deicer is an ionized solution with low electrical resistance. That is, electricity moves through the Deicer with less opposition than it does, for example, through water. As a precaution, airports were advised to evaluate the condition of their electrical systems.

The Port Authority of New York & New Jersey commissioned an independent study by Cable Technology Laboratories, Inc., to determine the cause of JFK's failures. The study found that the Deicer had no significant effect on cable insulation when compared to water and glycol-based deicers. However, the Deicer had a significant effect on the cable jackets because of its low electrical resistance, making the cables more susceptible to a phenomenon known as "tracking". Tracking is electrical leakage along the jacket caused by contaminants, such as water or chemicals, which have lower electrical resistance than jacket material. Tracking can cause hot spots and, in time, damage to underlying insulation.

Examination of cables revealed that defects in the cable jacket and insulation were due to tracking and the condition had existed for some time, well before this past winter's first use of the Deicer. Excess Deicer leaked into electrical systems and initiated faults at previously weakened locations.

CONCLUSION
The incident cited above is related to the low electrical resistance of the Deicer, not to any chemical reaction or corrosion between the cable and the Deicer. Airports using the Deicer or considering its use should evaluate their electrical systems to assure that the potential for Deicer entry into those systems is minimized. If electrical problems are noted, they should be fixed. And finally, winter operational plans should encourage "anti-icing" techniques to improve deicer performance and minimize chemical application.

We welcome any questions you may have regarding this or other technical matters. Feel free to contact our General Manager, Keith Johnson, at 712/526-2407; or contact our Fort Madison, Iowa plant at 800/346-7237.