Crossties are the heavy wooden beams that support the rails trains run on. Each tie is hewn from hardwood and measures 7” x 9” by 8’. Today, there are:
- More than 200,000 miles of railroad track in use in the United States
- Approximately 3,249 ties per mile
- Between 700 and 800 million ties in service
Borates protect wood from:
- Termites and other pests
- Moisture
- Rot
- Fungi
For decades, a dual borate-creosote preservative treatment has provided railroad crossties with long-lasting protection.
Questions have surfaced concerning boron’s effectiveness—particularly its potential for leaching. However, research continues to reinforce that dual treatment significantly extends the lifespan of railroad ties, especially in decay-prone areas.
Doubling the lifespan of railroad crossties
According to a paper published in Crossties magazine, “Dual treated ties last twice as long as ties with only the primary preservative in high decay hazard areas.”
With the right concentration and application, you can reduce replacement costs, ensure longevity, and keep critical transportation infrastructure safe.
What makes dual treatment so effective?
Dual treatment protects both the outer and inner layers of wood crossties—combining boron and creosote—to form a powerful preservative formulation.
First, producers treat the tie with a disodium octoborate tetrahydate (DOT) product such as
Tim-bor® Industrial. Because crossties are almost always made from a hardwood species, penetrating to the wood’s core is more difficult. But borates are highly water soluble, making deeper diffusion easier.
The crosstie then receives a pressure treatment of creosote (in certain situations, copper naphthenate). Creosote stays closer to the wood’s surface, equipping the wood with outer layer protection.
If only creosote is applied, a tie’s service life typically runs 8- 25 years. When crossties receive both borates and creosote, the dual protection extends the active lifespan to around 40 years.
Benefits of boron in railroad crossties
Boron compounds prevent moisture-induced decay, fungi-caused wood rot, and pest-related damage. In crossties, borates offer special advantages over other preservatives.
Reinforces strength
Borates’ ability to diffuse throughout wood prevents heartwood decay, a leading cause for crosstie failure. Left unchecked, fungi reduce the wood’s mass, lowering the tie’s strength and ultimately causing failure.
Slows “spike kill”
Degradation can also occur near the steel spikes securing rails to the wood ties. If that happens, the spikes may loosen, causing the rails to shift and in severe cases, train derailment occurs. Adding borates to the wood greatly lowers the risk of “spike kill.”
Safeguards from termites
Even after crossties are retired, borates safeguard the wood from termites and prevent these invasive pests from spreading to healthy wood during transportation.
U.S. Borax: Your source for high-quality borates
Just as railway companies count on the reliability of their crosstie producers, those producers count on the reliability and consistency of the borates they use to protect and preserve their ties.
The importance of a proper dual borate treatment can’t be understated. Dual treatment is not only economically efficient, but also critical to safe and reliable rail infrastructure. The right borates concentration, followed by a creosote treatment, can significantly extend railroad ties’ service life, even in areas prone to decay.
U.S. Borax Tim-bor Industrial delivers effective wood protection in a proven, reliably consistent and high-quality product.
Contact us
Our technical experts can help ensure your formulation meets American Wood Protection Association standards for protection and preservation. Because U.S. Borax products are subjected to robust quality management practices, you can trust that you’ll receive consistent, high-quality borates that perform well in your crosstie application.
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