Free Hazardous Location Tools

Interactive tools for engineers, facility managers, and procurement teams working with NEC hazardous location classifications and explosion-proof equipment. Everything here is free to use — no signup required.

ASHRAE math

Industrial Cooling Load Calculator

Calculate the cooling load (BTU/hr and tons) required for an industrial enclosure, control room, equipment shelter, or MCC building. Uses standard ASHRAE methodology with every calculation shown — engineers can verify the math step by step. Exportable to PDF, copyable, and shareable via URL.

  • ASHRAE-standard heat transfer methodology
  • 30+ US city design temperatures built in
  • Transparent math — every formula and number shown
  • Print to PDF, copy as report, or share by URL
Open the Cooling Load Calculator →
Step-by-step

Hazardous Location Classification Wizard

Don't know what classification your facility needs? Answer a few plain-English questions and this tool will identify the likely NEC Class, Division, and Group for the area you're trying to specify. Built for engineers AND non-engineers — every question explained, every result accompanied by reasoning.

  • Determines Class, Division, and Group
  • Plain-English explanations at every step
  • Handles "I don't know" answers gracefully
  • Surfaces ambiguity instead of hiding it
Open the Classification Wizard →
Two-way converter

NEC 500 ↔ Zone Classification Converter

Translate hazardous location classifications between the US system (NEC Article 500 — Class/Division/Group) and the international Zone system (NEC 505 / IEC / ATEX / IECEx). Handles the edge cases — Division 1 mapping to Zone 0 OR 1, IEC Group IIC covering US Groups A AND B — that simple tables hide.

  • Two-way translation between US and international
  • Plain-English explanation of every marking
  • Materials and example facilities for each combo
  • Full reference tables for Class I, II, III
Open the NEC Converter →

Need help specifying explosion-proof HVAC?

We design and modify explosion-proof air conditioning for every hazardous location classification. Most simple quotes back to you within 24–48 hours.