Another Coal Tar Sealer Extinction Factor: Fuel Resistant Alternatives

Sealcoaters around the country privately admit that the days of coal tar sealants are numbered. Long term users refer to it as a dinosaur facing extinction. While there are plenty of environmental and economic reasons for ending this product’s use, one of its previous performance distinctions, fuel resistance, is fading away as well. Here’s why.

The fuel resistance of coal tar is often cited by industry representatives as justification for the continued use of their product. It is true that gasoline and oil drips soften and degrade the quality of asphalt. That’s why pavements at gas stations are typically paved with white or gray concrete instead of black asphalt. Traditionally coal tar sealers create a fuel resistant barrier between asphalt and gasoline.

There are two new products emerging that will challenge this historic coal tar distinction.

Fuel Resistant Asphalt

For several years now, European pavement engineers have been working on fuel resistant asphalt (aka Polymer Modified Asphalt) for airport use. Earlier this year, the first use of this pavement was put into service at a US airport in Crestview, Florida. While test sections of this pavement have been used at Boston Logan International and LaGuardia International Airports, the Bob Sikes Airport in Crestview is the first full purpose use of fuel resistant asphalt in the United States. The mix is referred to P-401-FR.

The engineer for the project felt that the project had minimal risks. “It became evident pretty quickly that the risks were minimal, if any,” he recounted in an article in Airport Improvement Magazine. “This is not a brand-new product,” he emphasized. “This is not an untried, unproven material. Asphalt technology has come a long way. We’re using a performance-grade asphalt binder. A better binder is going to give you a better pavement. You know what you’re getting.”

The cost of the asphalt was an overall addition of 8% over a standard asphalt bid. Because the project was funded by the State of Florida, the project team got approvals from a variety of state agencies including the Florida Aviation Office.

Will this become an FAA (Federal Aviation Administration) standard? Perhaps. The Unified Facilities Guide, used by the Department of Defense, is reviewing this specification. The FAA has indicated that it will adopt the Guide, so when it does, then this will be an FAA standard.

Fuel Resistant, Non-Coal Tar Sealant

The second emerging advancement in fuel resistance is a product by Eco-star called TractionSeal FP. It tests out as non-detect for polycyclic aromatic hydrocarbons (PAH), dries fast and is fuel resistant.

So Why Are We Still Using Coal Tar Sealants?

So coal tar sealants are mutagenic, the main ingredient is carcinogenic, they cause negative effects on aquatic species, contaminate soil, elevate the level of toxins in house dust, are used around the US, will cost billions of dollars to clean up, and they have suitable cost-effective alternatives, but yet we still use them. Let’s hope for a quicker move toward extinction than what we have seen in the last 7 years!

Here’s a graphic showing a variety of sealers emersed in kerosene.