Mastering Cable Duct Sealing & Compliance on Filling Stations with the APEA & Energy Institute's “Blue Book”

When it comes to any installation on a Fuel Filling Station, one of the most essential references for Designers, Consultants, Engineers, Contractors and enforcement Officers is the “Blue Book”, meticulously crafted and maintained by the Association for Petroleum & Explosive Administration (APEA) in collaboration with the Energy Institute.

What Exactly is the “Blue Book”?
The “Blue Book” is a comprehensive manual jointly authored by APEA and the Energy Institute. This invaluable resource outlines everything you need to know about the design, construction, modification, maintenance, and decommissioning of filling stations. In essence, it serves as the holy grail for all activities on Fuel Filling Stations.

The “Blue Book's” Contribution to AC Cable Solutions
Our commitment at AC Cable Solutions to providing the best possible duct sealing solutions is deeply rooted in our adherence to the guidelines laid out in the “Blue Book”. This indispensable guide has played a pivotal role in shaping our products - DuctSeal LG, DuctSeal HG, and Greystuff. It provides authoritative recommendations regarding the technology and materials that should be employed. As a result, we, along with all contractors in this field, follow these guidelines rigorously when it comes to sealing cable ducts.

Why should a cable duct be sealed on a Fuel Filling Station?
Fuel Filling Stations are integral to our daily lives, providing us with the fuel needed to power our vehicles. However, they can also be potentially hazardous environments due to the presence of flammable liquids, vapours, and gases. One often overlooked and/or inappropriately selected safety measure is the sealing of below-ground cable ducts on fuel filling stations. In this blog, we will explore why it is essential to seal these ducts as recommended in the “Blue Book” to prevent the transfer of flammable substances between hazardous and non-hazardous areas and ingress into building structures or equipment, ensuring the safety of both people and property on the site.

Understanding the Risks
Fuel Filling Stations are filled with numerous sources of ignition, from running vehicles to static electricity, making them high-risk areas for fires and explosions. Flammable liquids, such as petrol and diesel, can easily spill during refuelling or due to accidents. These spills can lead to the formation of flammable vapours, which can travel significant distances and pose a danger to anyone in the vicinity.

Cable Ducts: A Potential Pathway for Hazards
Cable ducts are installed below the forecourt and traffic surfaces of Fuel Filling Stations to carry electrical and communication cables and pneumatic lines for various equipment, including fuel dispensers, tank monitoring systems, lighting, and security systems. While these ducts are essential for ensuring smooth operations, they can also serve as pathways for the transfer of flammable liquids, vapour, and gases between potential spillage areas and buildings or other confined spaces on site.

Sealing at the Point of Entry
Sealing cable ducts at the appropriate point in a below-ground draw chamber is crucial to prevent the intrusion of flammable substances. When a spill occurs, flammable liquids and vapour can seep into cable ducts through liquid and vapour pathways. Once inside, these substances can travel to other areas, increasing the risk of ignition. Proper sealing ensures that the ducts are impermeable to such substances, preventing their spread.

Choosing the Right Sealing Materials
The choice of sealing materials is critical in ensuring the effectiveness of duct sealing. It is essential to use materials that are resistant to the chemicals present in fuel and can withstand the environmental conditions on a petrol station forecourt. Common sealing materials include sealants, gaskets, and mechanical collars designed specifically for this purpose.

Regular Maintenance and Inspection
Once the ducts are sealed, regular maintenance and inspection are necessary to ensure their continued effectiveness. Over time, wear, and tear, as well as additional work and maintenance activities, can result in changes in environmental conditions, that can compromise the integrity of the seals. Routine inspections should be conducted to identify and address any issues promptly.

What products can be used to seal cable ducts on a Fuel Filling Station
Any duct sealing system used must be able to show clear test evidence that the product can resist hydrocarbons that are generally present on a fuel Filling Station. Some of these hydrocarbons are listed below, but not completely exhaustive, and each site should be treated separately.  

• Petrol
• Diesel
• Ethanol
• LPG Gas
• HVO Synthetic fuel
• AdBlue®

Examples of the most common seals installed within the ducts are the following:

Duct Seal LG
Introducing the Duct Seal LG Cable Duct Sealing System from AC Cable Solutions, a leading choice for effectively sealing cable ducts. This system is highly favoured for its compatibility with cables under 25mm in overall diameter, making it an ideal solution for a wide range of cable sizes commonly encountered in petroleum station forecourts.

At the heart of this system lies the exceptional sealant known as "GreyStuff," which has undergone rigorous testing to ensure its resilience against hydrocarbons. Beyond its chemical resistance, GreyStuff also exhibits remarkable microbial resistance, effectively inhibiting the growth of bacteria, mould, and fungi on the sealant's surface. This feature is particularly valuable, given that duct entry points are frequently located in damp, stagnant environments.

Duct Seal HG
Duct Seal HG, powered by the same outstanding GreyStuff sealant, takes duct sealing to the next level by accommodating a wide spectrum of cable sizes, from the smallest cables to large, heavy power cables or pipes. What sets this system apart is its innovative rubber sleeve backing system, designed to envelop and support the cables, delivering robust support.

This unique sealing approach not only ensures hydrocarbon resistance but also provides exceptional pressure resistance, withstanding pressures of up to 2.0 bar. DuctSeal HG is the ultimate solution for sealing and securing your ducts, offering versatility, strength, and protection in one comprehensive package.

Conclusion
The sealing of cable ducts on Fuel Filling Station is a vital safety measure that should not be overlooked. Preventing the transfer of flammable liquids, vapour, and gases through these ducts can significantly reduce the risk of fires and explosions, protecting both people and property on the site. Sealing systems dictated in the “Blue Book”, create a robust barrier against potential hazards. By choosing the right sealing materials and conducting regular maintenance, Filling station owners can contribute to a safer and more secure environment for all.

Safety should always be a top priority, and sealing cable ducts is a small yet significant step in achieving it at Fuel Filling Stations.

Written by Carl Pike - The Duct Sealing Man