Smarter Emission Solutions for a More Efficient U.S. Workboat Fleet

For over 40 years, Hug Engineering has been a trusted name in exhaust-gas aftertreatment industry - known for high-performance SCR and DPF systems that keep workboats compliant, reliable, and cost-efficient. With a long-standing footprint in the U.S. power generation market and decades of proven marine expertise, we are uniquely positioned to support America’s workboat industry with reliable, compliant aftertreatment solutions. That’s exactly why our participation at the International WorkBoat Show in New Orleans matters to us: it’s an opportunity to share our experience, and show how our solutions help operators and shipyards meet the unique regulatory and operational challenges of the American market.

At Hug, we don’t believe in one-size-fits-all. Every workboat, engine room, and operational profile is different - and that’s where our engineering approach stands out. Our systems are built to fit complex spaces, operate reliably in harsh 24/7 environments, and respect the certification frameworks that matter most in the U.S.: EPA Tier 4, IMO Tier III, and California’s CARB At Berth requirements.

Meeting U.S. Regulations with an Integrated Solution

The U.S. regulatory landscape places strong pressure on NOₓ and PM emissions - and every operator knows how quickly compliance influences tender eligibility, operating permissions, and long-term fleet value.

EPA Tier 4 Compliance (U.S.-Flagged Vessels)

EPA Tier 4 is mandatory for American-registered workboats above certain power ranges. While certification lies with the engine manufacturer, Hug provides the aftertreatment technology needed to reach the required emission limits.

Our SCR and DPF solutions are:

• Extremely compact, enabling integration even in tight engine rooms
• Highly flexible, with customizable layouts for retrofits and newbuilds
• Engine-friendly, with very low backpressure to minimize the fuel consumption increase (a major advantage when engines run thousands of hours per year) 

IMO Tier III

Any foreign vessel entering ECA zones must comply with IMO Tier III - making it relevant for international fleets, offshore vessels, and support craft operating in the Gulf or East Coast.

Our SCR systems for IMO Tier III are:

• Certified for more engine brands than other alternatives
• Switchable outside ECA zones, reducing urea consumption and increasing operating range
• Built with up to 20,000-hour catalysts, minimizing maintenance and downtime 

CARB At Berth (California)

One of the strictest regional regulations in the world, CARB At Berth requires NOₓ and PM levels comparable to shore power. To meet this, vessels need deep emission reduction, far beyond standard IMO III or EPA Tier 4.

Hug offers a single compact solution:

• DPF + SCR + Silencer (optional) integrated into one unit
• Up to 99% PM reduction (DPF) and ultra-low NOₓ (SCR)
• Fully automated DPF regeneration for dependable operation 

CARB At Berth-compliant systems require engineering depth and emissions expertise that few companies can offer - and this is exactly where Hug’s experience becomes a major advantage. 

Solving Real Problems Workboat Operators Face

Every conversation we’ve had with U.S. operators touches the same concerns - and they match precisely what we see worldwide.

1. Space constraints

Engine rooms are cramped. Retrofits are complex.
Hug designs systems around your existing space, not the other way around - including vertical/horizontal reactor layouts and integrated silencers if required. 

2. Backpressure & fuel consumption

Higher backpressure = higher fuel consumption = higher cost

Thanks to exceptionally low system backpressure, Hug solutions keep the engine breathing freely - minimizing the additional fuel consumption and delivering significant long-term cost advantages.

3. Urea logistics & OPEX

Switchable SCR operation means:

• full compliance inside ECA zones
• urea savings outside, reducing tank size and extending range

4. Integration complexity

Shipowners always worry about: “Will it fit? Will it interfere with operations?” To ease this burden and allow you peace of mind, our team delivers:

• 3D integration models
• backpressure calculations
• optimized layouts
• fast and clean installation support

“It never fits at first glance - but that’s exactly where we excel.” 

Peter Zijdemans - Head of Workboat Business Unit

Why Workboat Customers Choose Hug

Based on decades of hands-on projects - from tugboats to offshore support vessels - customers choose Hug because of:

• Reliable performance under harsh marine conditions
• Durable quality (20+ years of typical system life)
• Highly flexible layouts for newbuilds and retrofits
• Certification expertise with classification societies worldwide
• Prepared for future fuels (methanol, LNG, hydrogen)
• Support from both European and U.S. teams

Operators frequently approach Hug directly when upgrading IMO Tier I or II vessels to Tier III - because they know we can make their installation work even in extremely tight spaces. 

See Us in New Orleans – Booth 3863

We will exhibit at the International WorkBoat Show, bringing together experts from our European headquarters and our U.S. team. 

Whether you’re planning a newbuild, modernizing an existing vessel, or preparing for stricter EPA/CARB requirements, we invite you to pass by, meet the team, and explore how Hug can help you operate cleaner, more efficiently, and with total confidence in compliance.

📍 Booth 3863
📅 December 3–5, 2025 — New Orleans
📞 Peter Zijdemans | peter.zijdemans@hug-engineering.com

We look forward to meeting you - and to building solutions that work for your fleet, your business, and the future of cleaner maritime operations.