From crude oil, ethanol, chemicals, LPG, and everything in between, railcars move an enormous volume of product across Western Canada every day. But not every tank car is built the same, and not every loading system should be either. In other words, the equipment, safety controls, and regulatory requirements for a pressurized LPG railcar look very different from what you need for a non-pressurized option.

At Northern Platforms, we help industrial operators across Western Canada design and install turnkey loading solutions engineered for their specific application. We have experience with both pressurized and non-pressurized systems. Keep reading to learn more about how these systems are different and how we can help.

Understanding Tank Car Types 

Before diving into equipment, it helps to understand the fundamental distinction between the two main categories of tank cars.

Non-Pressurized (General Service) Tank Cars

Non-pressurized tank cars, marked as TC-117 in Canada, are general service vessels designed to carry materials at pressures typically below 25 psi. These cars transport a wide range of products, including:

• Agricultural commodities
• Diesel fuel and petroleum products
• Crude oil and ethanol
• Food-grade liquids
• Non-hazardous chemicals

These cars typically feature visible fittings and valves at the top, and may also include a bottom outlet valve for unloading. Their design is more straightforward, and loading operations are generally less complex than those of pressurized systems.

Pressurized Tank Cars

Pressurized tank cars, designated by TC-105 and TC-112 in Canada, are purpose-built vessels used to transport liquefied compressed gases under pressure, typically above 40 psi. Products commonly transported in pressurized tank cars include:

• LPG (liquefied petroleum gas) — propane and butane
• Anhydrous ammonia
• Chlorine
• Other liquefied gases and high-hazard materials

These cars feature heavy-duty protective housings over their fittings, steel jackets, and thermal protection systems designed to prevent catastrophic failure in the event of a fire or accident. The key reason LPG must be transported in pressurized cars? Propane and butane exist as liquids only when kept under pressure. The moment that pressure is compromised, the liquid can flash back into a gas.

Loading Systems for Non-Pressurized Tank Cars

Non-pressurized loading operations are the more common of the two configurations. The products involved, such as crude oil, ethanol, diesel, and chemicals, are typically at or near atmospheric pressure, which makes the loading system design more forgiving.

Transfer Equipment

For non-pressurized service, operators can choose from a range of transfer options, including standard top-loading arms, bottom-loading systems, or reinforced flexible hoses. The primary engineering priorities for non-pressurized loading are flow rate, material compatibility, and reach.

Vapor Management

Depending on the product, non-pressurized loading may allow for open venting or vapour balancing rather than full closed-loop vapour recovery. Environmental regulations still govern allowable emissions, but the system architecture is significantly less complex than what’s required for LPG.

Platform and Access

Regardless of what product you are transferring, worker access to the top of a non-pressurized tank car still requires a proper loading platform, gangway, and fall protection. These railcar loading platforms are typically purpose-built to accommodate the types of locomotives you deal with most frequently.

Regulatory Requirements

Non-pressurized loading operations are subject to Transport Canada’s Transportation of Dangerous Goods Act and relevant provincial OHS regulations. Alberta’s OHS Code and WorkSafeBC both require fall protection for workers at heights of three metres or more. Other regulations and requirements vary depending on the type of product that you are dealing with.

Loading Systems for Pressurized Tank Cars

Loading LPG into a pressurized railcar isn’t simply a matter of connecting a hose and opening a valve. The high-pressure, volatile nature of LPG demands a system built from the ground up for these conditions.

Transfer Equipment

The LPG loading arm is the heart of any pressurized railcar loading station. The best systems for railcar applications include:

• High-pressure construction: Carbon steel or stainless steel rated for LPG service pressures
• Counterbalanced swivel joints: Allow smooth, ergonomic movement so a single operator can position the arm without strain
• Leak-resistant sealing systems: Engineered to prevent drips, leaks, and emissions at connection points
• Integrated vapour recovery ports: Support a closed-loop system to capture displaced vapours during loading
• Emergency breakaway safety couplers: Automatically disconnect and seal in the event of an unexpected railcar rollaway
• NFPA 58-compliant design: Meets the Liquefied Petroleum Gas Code for safe LPG handling

We’ve highlighted the best LPG loading arms in a previous article. For more details about these systems, read it here: “4 Top-Loading Arms for LPG and Sulfur Loading Applications.”

Vapor Management

Pressurized LPG loading requires a fully closed-loop vapour recovery system. As liquid LPG is pumped into the tank car, displaced vapours must be captured and routed back into the storage system. This prevents both environmental emissions and dangerous vapour accumulation around the loading platform.

A properly specified LPG loading arm integrates vapour recovery capability directly into the transfer system, maintaining a sealed circuit from storage tank to railcar throughout the entire loading cycle.

Platform and Worker Access

As with non-pressurized operations, a proper loading platform, gangway, and fall protection system are required. For LPG, this also includes a safety cage surrounding the operator at the top of the railcar during connection and disconnection.

Emergency Controls

Automatic emergency shutoff valves are mandatory for pressurized LPG service under NFPA 58. These valves immediately halt product flow in the event of a detected leak, fire, or unexpected railcar movement. In addition, a grounding and bonding system is required to eliminate static discharge risk.

Regulatory Requirements

Any facility loading LPG must comply with NFPA 58, the Liquefied Petroleum Gas Code. In Canada, the Transportation of Dangerous Goods (TDG) Act and the Liquefied Petroleum Gases Bulk Storage Regulations may also apply.

Top Loading and LPG Loading Arms from Northern Platforms

Whether you’re loading general service products or high-pressure LPG, Northern Platforms is your single source for railcar loading arms across Western Canada. As an authorized distributor of OPW Engineered Systems, we carry the full line of top-loading arm configurations, and we have the application expertise to match the right arm to your product, your railcar type, and your site.

Our loading arm inventory includes:

• Boom-Style (Supported and Unsupported) Loading Arms: Available in 2″, 3″, 4″, and 6″ sizes in carbon steel, stainless steel, or aluminum. Built for variable-reach applications and ideal for both LPG and general service railcar loading. Folds back against the platform for compact storage.
• Bullhorn (Dual Connection) Loading Arms: The preferred configuration for pressurized LPG railcars, providing dual product connections from a single standpost to accommodate two liquid lines and a vapour recovery line.
• Scissor Style Loading Arms: Designed for tanker truck loading applications with a secondary arm that rotates 360° in the horizontal plane, offering a spotting allowance nearly twice its length.
• Fixed Reach Style Loading Arms: A simplified three-swivel design for straightforward top-loading applications. Available with an optional outboard valve to reduce drips and leaks on viscous products.
• Custom Insulation Packages: For temperature-sensitive loading applications like molten sulphur, fully removable and reusable, available in top and bottom designs.

We’ve been supplying and installing railcar loading systems across Alberta and BC for over 20 years. Whether you need a single replacement arm or a complete turnkey loading station, our team will make sure you get the right equipment for your application.

Get a Quote from Northern Platforms

Ready to add a new railcar loading arm to your site or upgrade your complete loading station? Our team will assess your site, recommend the right configuration, and provide a transparent quote.

Call our office or request more information through our website today!