4-Gas Detectors

4-Gas Detectors

4-Gas Detectors – Reliable Multi-Gas Monitors for Confined Space & Industrial Safety

A 4-gas detector (also called a 4-gas monitor or multi-gas detector) is essential personal protective equipment that continuously measures four critical atmospheric hazards in real time:

  • LEL (Lower Explosive Limit) – detects combustible gases and vapors to prevent explosions
  • O2 (Oxygen) – alerts to deficiency (asphyxiation risk) or enrichment (fire hazard)
  • H2S (Hydrogen Sulfide) – toxic "rotten egg" gas common in sewers, oil & gas, and wastewater
  • CO (Carbon Monoxide) – the invisible, odorless "silent killer" from incomplete combustion

These portable devices provide instant readings, loud audible alarms (90+ dB), flashing visual alerts, vibration notifications, TWA/STEL tracking, and often datalogging or Bluetooth connectivity — helping keep workers safe in high-risk environments like confined spaces, refineries, utilities, construction sites, firefighting, and general industrial operations.

Diffusion vs. Pumped 4-Gas Detectors: Which Type Fits Your Needs?

Choosing between diffusion and pumped models depends on your application:

  • Diffusion 4-Gas Detectors (ambient air sampling, no internal pump) — Lightweight, compact, and ideal for continuous personal monitoring in the OSHA-defined breathing zone. Perfect for most daily use. Explore our Diffusion 4-Gas Detectors — featuring top models like the ultra-compact RKI GX-3R (world's smallest at just 3.52 oz), MSA Altair 4XR, Honeywell BW Icon, and more.
  • Pumped 4-Gas Detectors (internal pump draws air through tubing) — Essential for pre-entry sampling in tanks, manholes, sewers, or confined spaces where remote testing is required. View Pumped 4-Gas Detectors — including Honeywell BW Max XT II, Industrial Scientific Ventis Pro5 Pumped, and GMI PS241.

Why Choose Ideal Calibrations for Your 4-Gas Detector?

Based in Melvindale, Michigan, we don't just sell detectors — we live and breathe gas detection safety. We manufacture our own precision calibration gas blends in-house (NIST-traceable and compatible with all major brands), including popular always-stocked 4-gas mixes.

Benefits of shopping with us:

  • Expert in-house calibration, repair, and sensor replacement services — fast local turnaround
  • Stocked inventory of top brands: RKI Instruments, MSA, Industrial Scientific (ISC), Honeywell BW Technologies, and more
  • Competitive pricing, fast shipping, and bulk/custom options
  • Real support from people who calibrate and service these units daily

Browse our full selection of 4-gas detectors below — diffusion and pumped models, plus accessories like regulators, probes, and 4-component calibration gas. Not sure which one is right for you? Contact us or check our 4-gas detector FAQ — we're here to help!

All detectors shown are ready for immediate use with our reliable calibration support. Stay safe out there.

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