The Smart Shift: Designing for Durability with the Nitrogen‑Pac™ M Series

Dry and preaction sprinkler systems are often installed to protect critical infrastructure but the real threat frequently comes from within: oxygen-driven corrosion.

Every fill and trip introduces moisture and oxygen, starting a corrosion process that compromises piping, triggers leaks, and reduces reliability over time. Engineers know this. Contractors see it in the field. The question is no longer if corrosion is occurring but what you’re doing to prevent it.

That’s why more professionals are shifting to on-site nitrogen generation.

Designed for Code, Built for Performance

The Nitrogen-Pac™ M Series from United Fire Systems is a modular nitrogen generation and fill system designed specifically for dry and preaction sprinkler applications. Built with input from real-world contractors, this solution meets engineering expectations across the board:

• Delivers 98+% nitrogen purity, compliant with NFPA 13 Annex D corrosion mitigation guidance
• Maintains a –40°F dew point, minimizing internal system moisture
• Complies with system pressurization time limits (30 min fill per NFPA 13 Section 8.2.6.7)

Whether designing new or retrofitting, the M Series satisfies code and delivers performance that exceeds basic compliance.

Why Nitrogen and Why Now?

According to testing from FM Global and the Army Corps of Engineers, corrosion rates drop by 90% or more when systems are pressurized with nitrogen instead of compressed air.

Compressed air introduces:

• ~21% oxygen
• Water vapor
• Accelerated MIC conditions

Nitrogen eliminates:

• Internal oxidation of pipe walls
• Risk of premature system failure
• Need for constant repairs or pipe replacement

If your system design includes galvanized piping or is protecting mission-critical facilities, switching to nitrogen is no longer optional, it’s essential.

Modular Simplicity with Field-Proven Capacity

Contractors benefit from the modular design, which allows for:

• Generator module installation without electrical connection
• Space-saving, flexible layouts for tight mechanical rooms
• Support for up to 31,100 gallons of sprinkler pipe volume

Plus, there’s no need to manage high-pressure cylinders or worry about gas delivery delays. The M Series generates nitrogen directly from ambient air, 24/7.

Engineered for Better Specs and Better Results

Whether you’re writing specs for a high-rise or overseeing corrosion-prone retrofits, the Nitrogen-Pac™ M Series offers:

• Code alignment
• Corrosion mitigation
• Ease of installation
• Operational reliability

This is more than a compressor, it’s an engineered system for long-term protection and professional peace of mind.

References:

NFPA 13 (2022 & 2025 Editions) – Section 8.2.6.7 (System Filling Time Requirements) and Annex D (Corrosion Mitigation)

FM Global Data Sheet 2-1, Corrosion in Automatic Sprinkler Systems, April 2018

Army Corps of Engineers (ERDC/CERL TR-13-21), Microbiologically Influenced Corrosion (MIC) in Fire Sprinkler Systems, 2013

National Fire Sprinkler Association (NFSA) – TechNotes & Updates on Corrosion, Nitrogen Use, and 2025 Code Changes

Written By:

Ashley Villa

Marketing Manager

avilla@ufpco.com