Nitrogen 400 Calibration Gas — Complete Guide and Buy Direct

Nitrogen 400 calibration gas (400 ppm Nitrogen Dioxide / NO₂ balance Nitrogen) is one of the most searched calibration gas mixtures in the United States, with over 18,000 searches per month from safety professionals, industrial hygienists, and gas detection technicians.

This guide covers everything you need to know about Nitrogen 400: what it is, which detectors it calibrates, how to choose the right cylinder size, and how to buy it directly from an ISO 17025:2017 accredited laboratory — without paying distributor markups.

What Is Nitrogen 400 Calibration Gas?

Nitrogen 400 refers to a calibration gas mixture containing 400 parts per million (ppm) of Nitrogen Dioxide (NO₂) balance Nitrogen (N₂). It is used as a reference standard to verify and calibrate gas detection instruments that measure toxic nitrogen dioxide concentrations in industrial environments.

The "400" designation indicates the concentration: 400 ppm NO₂. This concentration is commonly specified by:

•       OSHA for short-term exposure limit (STEL) calibration at 1 ppm working environments

•       Industrial hygienists monitoring welding fumes, engine exhaust, and combustion byproducts

•       Environmental testing laboratories requiring NIST-traceable reference standards

•       Fixed gas detection systems in chemical plants, tunnels, and enclosed spaces

Where Is Nitrogen 400 Used?

Available Cylinder Sizes for Nitrogen 400

Trigas USA supplies Nitrogen 400 calibration gas in the following disposable cylinder sizes. All cylinders are non-refillable, DOT-compliant, and shipped with a Certificate of Analysis.

Nitrogen 400 Cross-Reference — Equivalents for Gasco, Calgaz, and Portagas

If you currently use Nitrogen 400 from another supplier, Trigas USA is a certified direct equivalent. Our gas mixtures are manufactured to the same NIST-traceable specifications with ISO 17025:2017 laboratory accreditation.

Important: Trigas USA is an independent ISO 17025:2017 accredited manufacturer — not affiliated with Air Liquide, Airgas, or Linde. This means your calibration program is not dependent on a single corporate supply chain.

Why ISO 17025:2017 Accreditation Matters for Your Nitrogen 400 Purchase

Not all calibration gas suppliers hold laboratory accreditation. ISO 17025:2017 is the international standard for testing and calibration laboratories — it requires:

•       Documented measurement traceability to national standards (NIST)

•       Independent third-party audits of laboratory processes and equipment

•       Uncertainty quantification on every Certificate of Analysis

•       Competency verification for all technical personnel

•       Equipment calibration records maintained and available upon request

Trigas USA holds: ISO/IEC 17025:2017 (L25-1002) · ISO 17034:2016 (L25-1003) · PJLA Accreditation #125017 · EPA PGVP Certification #29.

For OSHA-regulated environments, EPA Part 75 compliance programs, and pharmaceutical laboratories, ISO 17025-accredited calibration gas is not optional — it is required documentation for instrument qualification and audit defense.

Shelf Life and Storage for Nitrogen 400 Cylinders

Nitrogen dioxide (NO₂) is a reactive gas that can degrade in storage. Following proper handling procedures extends cylinder life and ensures measurement accuracy.

Shelf Life

•       34L and larger cylinders: 12 months from date of manufacture

•       17L cylinders: 6 months from date of manufacture

•       Every Trigas USA cylinder includes the manufacture date and expiration date on the label

Storage Requirements

•       Store upright in a cool, dry location away from direct sunlight

•       Temperature: 40°F to 104°F (4°C to 40°C)

•       Do not store near heat sources, oxidizing agents, or corrosive chemicals

•       Keep away from flame and ignition sources

•       Secure cylinder with chain or strap to prevent tipping

Bump Test Frequency

Most detector manufacturers recommend bump testing before each use. For continuous-duty instruments, a daily bump test with Nitrogen 400 calibration gas ensures your NO₂ sensor responds correctly before personnel enter hazardous environments.

How to Order Nitrogen 400 from Trigas USA

Ordering directly from Trigas USA eliminates distributor margins and ensures your cylinder comes directly from the manufacturing laboratory with full chain-of-custody documentation.

Option 1 — Single Purchase

•       Visit trigasusa.com/shop and select Nitrogen 400

•       Choose cylinder size (17L, 34L, 58L, 103L)

•       Add to cart and checkout — all major credit cards accepted

•       Certificate of Analysis and SDS included with every shipment

•       Same-day shipping on orders placed before 2:00 PM EST

Option 2 — Auto-Replenish Subscription (Save 8%)

•       Select your cylinder size and calibration frequency

•       Choose delivery interval: every 30, 60, or 90 days

•       Receive automatic reminder 14 days before delivery

•       8% discount on every order + free shipping

•       Cancel or pause anytime from your account dashboard

Option 3 — B2B Account with Net-30 Terms

•       Apply for a Trigas USA business account at trigasusa.com/b2b

•       Approval within 1 business day for qualified companies

•       Purchase orders accepted — invoice on Net-30 terms

•       Dedicated account manager for EHS and safety coordinators

•       Volume pricing available for orders of 10+ cylinders

Shipping Information — Nitrogen 400 Calibration Gas

Nitrogen 400 calibration gas cylinders are classified as Division 2.3 (toxic gas) and Division 2.2 (non-flammable compressed gas) materials under DOT 49 CFR. Trigas USA is certified for HazMat shipping via ground carriers.

•       Carrier: UPS Ground HazMat Certified

•       Transit time: 1–5 business days depending on destination

•       Packaging: DOT-compliant HazMat packaging with required labels

•       Documentation: SDS, CoA, and shipping manifest included

•       Restrictions: Cannot ship to P.O. boxes. Air shipping not available for pressurized cylinders

Frequently Asked Questions — Nitrogen 400 Calibration Gas

Is Nitrogen 400 the same as 400 ppm NO₂ in nitrogen?

Yes. "Nitrogen 400" is a shorthand designation for a calibration gas mixture containing 400 parts per million of Nitrogen Dioxide (NO₂) with the balance being pure Nitrogen (N₂). The full name is "400 ppm NO₂ balance N₂."

What regulator do I need for a Nitrogen 400 cylinder?

Most Trigas USA Nitrogen 400 cylinders use a CGA 600 connection. You will need a compatible demand-flow or fixed-flow regulator with CGA 600 inlet. We sell compatible regulators separately at trigasusa.com/regulators.

Can I use Trigas USA Nitrogen 400 instead of Gasco or Calgaz?

Yes. Trigas USA Nitrogen 400 is a certified equivalent to Gasco, Calgaz, Portagas, and Norlab Nitrogen 400 mixtures. Our gas is manufactured to the same concentration specification with ISO 17025:2017 accreditation and NIST-traceable CoA.

How do I verify my Nitrogen 400 cylinder is still good?

Check the expiration date printed on the cylinder label. If the cylinder is past its expiration date, do not use it for calibration. Expired gas may have degraded concentration accuracy. Contact us at orders@trigasusa.com to arrange a replacement.

Does Trigas USA offer same-day shipping?

Yes. Orders placed before 2:00 PM EST Monday–Friday are processed same day. Delivery time depends on your location — Southeast USA typically receives orders in 1–2 business days.

Related Products and Resources

•       4-Gas Calibration Cylinder (CO / H₂S / O₂ / LEL) — trigasusa.com/4-gas-calibration

•       CO Calibration Gas — Carbon Monoxide reference standards

•       H₂S Calibration Gas — Hydrogen Sulfide disposable cylinders

•       CGA 600 Regulators — Compatible with all Trigas USA cylinders

•       Bump Test Gas Guide — How often to bump test your gas detector

•       ISO 17025 vs NIST Traceable — What the difference means for your calibration program

ISO/IEC 17025:2017 Accredited (L25-1002) · ISO 17034:2016 (L25-1003) · EPA PGVP #29 · P