{
  "slug": "r-438a",
  "displayName": "R-438A",
  "altSpellings": [
    "R438A",
    "438A",
    "Genetron MO99"
  ],
  "chemicalName": "Five-component HFC blend with hydrocarbons",
  "chemicalFormula": "R-32/R-125/R-134a/R-600/R-601a (8.5/45/44.2/1.7/0.6)",
  "ashraeNumber": "R-438A",
  "type": "hfc-blend",
  "safetyClass": "A1",
  "tradeNames": [
    {
      "name": "Genetron MO99",
      "manufacturer": "Honeywell"
    }
  ],
  "composition": [
    {
      "component": "R-32",
      "massFraction": 0.085
    },
    {
      "component": "R-125",
      "massFraction": 0.45
    },
    {
      "component": "R-134a",
      "massFraction": 0.442
    },
    {
      "component": "R-600",
      "massFraction": 0.017
    },
    {
      "component": "R-601a",
      "massFraction": 0.006
    }
  ],
  "physical": {
    "boilingPointC": -43,
    "boilingPointF": -45.4,
    "critical": {
      "tempC": 84.5,
      "tempF": 184.1,
      "pressurePsia": 599,
      "pressurePsig": 584,
      "pressureKpaA": 4127,
      "pressureKpaG": 4026
    },
    "molarMassGPerMol": 99.1,
    "liquidDensityKgPerM3At25C": 1153,
    "temperatureGlideF": 12.6,
    "hasSignificantGlide": true
  },
  "environmental": {
    "odp": 0,
    "gwp100Ar5": 2265,
    "gwp100Ar6": 2440,
    "atmosphericLifetimeYears": null,
    "snapStatus": "Listed for R-22 retrofit; AIM Act phase-down affected"
  },
  "lubricants": {
    "compatible": [
      "MO",
      "AB",
      "POE"
    ],
    "incompatible": [],
    "notes": "Hydrocarbon components aid miscibility with mineral oil. Marketed by Honeywell as a 'no oil change' R-22 retrofit."
  },
  "applications": [
    "R-22 retrofit (commercial AC, refrigeration)",
    "Compatible with mineral oil systems"
  ],
  "replacementOptions": [
    "r-32",
    "r-454b"
  ],
  "replaces": [
    "r-22"
  ],
  "regulatoryStatus": {
    "epaPhaseoutComplete": false,
    "epaPhaseoutDate": null,
    "aimActAffected": true,
    "snapApproved": true
  },
  "ptChart": [],
  "dataSource": {
    "ptChartSource": "Manufacturer datasheet: Honeywell Genetron Performax LT (R-438A) Technical Information",
    "ptChartGeneratedAt": "2026-06-05T07:54:28.517Z",
    "ptChartVerifiedAgainst": [
      "Honeywell Genetron MO99 technical datasheet"
    ],
    "propertiesSource": "Honeywell Genetron MO99 datasheet + ASHRAE Standard 34-2022",
    "gwpSource": "IPCC AR5 Table 8.A.1 (composition-weighted)",
    "dataStatus": "manufacturer-datasheet-published",
    "primarySources": [
      {
        "type": "manufacturer-datasheet",
        "citation": "Honeywell International Inc., Genetron Performax LT (R-438A) Technical Information / Material Data Sheet.",
        "url": "https://www.honeywell-refrigerants.com/americas/",
        "scope": "Published PT chart and physical property data for R-438A retrofit refrigerant."
      },
      {
        "type": "standards",
        "citation": "AHRI Standard 700-2019 Specifications for Refrigerants — R-438A specification entry.",
        "url": "https://www.ahrinet.org/search-standards"
      }
    ]
  }
}