{
 "license": "CC BY 4.0 — Tremon Solutions, https://www.tremon.nl/gases/co",
 "generated": "2026-09-17",
 "key": "co",
 "name": "Carbon monoxide",
 "formula": "CO",
 "formula_plain": "CO",
 "iupac": "carbon monoxide",
 "synonyms": [
  "Carbon oxide",
  "Flue gas",
  "Monoxide"
 ],
 "cas": "630-08-0",
 "ec_number": "211-128-3",
 "un_number": "1016",
 "un_shipping_name": "Carbon monoxide, compressed",
 "transport_class": "2.3 (Toxic gases)",
 "pubchem_cid": 281,
 "molar_mass_g_mol": 28.01,
 "mg_m3_per_ppm_20c": 1.16,
 "boiling_point_c": -191.5,
 "sublimation_point_c": null,
 "melting_point_c": -205.07,
 "critical_temp_c": -140.2,
 "critical_pressure_bar": 34.99,
 "vapour_pressure_bar": null,
 "vapour_pressure_at_c": null,
 "density_gas_kg_m3": 1.2506,
 "density_condition": "0 °C, 1013 mbar",
 "relative_density_air": 0.97,
 "solubility_water": "35,5 ml/l at 0 °C",
 "appearance": "compressed gas, colourless, odourless",
 "odour": "odourless",
 "chemical_character": [
  "Extremely flammable gas. Forms hazardous explosive mixtures with air.",
  "Gas is lighter than air.",
  "Acute or chronic health hazards result from the substance.",
  "(see: chapter REGULATIONS)."
 ],
 "hazard_class": "toxic + flammable",
 "ghs_classification": [
  "Flammable gases, Category 1; H220",
  "Gases under pressure, compressed gas; H280",
  "Acute toxicity, Category 3, inhalation; H331",
  "Reproductive toxicity, Category 1A; H360D",
  "Specific Target Organ Toxicity (repeated exposure), Category 1; H372"
 ],
 "ghs_signal_word": "Danger",
 "ghs_hazard_statements": [
  "H220: Extremely flammable gas.",
  "H280: Contains gas under pressure; may explode if heated.",
  "H331: Toxic if inhaled.",
  "H360D: May damage the unborn child.",
  "H372: Causes damage to organs through prolonged or repeated exposure."
 ],
 "euh_statements": [],
 "nfpa704": {
  "health": 3,
  "flammability": 4,
  "instability": 0,
  "special": null
 },
 "lel_vol_pct": 11.3,
 "uel_vol_pct": 75.6,
 "autoignition_c": 605.0,
 "temperature_class": "T1",
 "explosion_group": "IIA",
 "eu_ioelv": {
  "twa_8h_ppm": 20.0,
  "twa_8h_mg_m3": 23.0,
  "stel_15min_ppm": 100.0,
  "stel_15min_mg_m3": 117.0,
  "directive": "Directive 2022/431/EU"
 },
 "de_agw": {
  "twa_ppm": 20.0,
  "twa_mg_m3": 23.0,
  "source": "TRGS 900 via GESTIS"
 },
 "nl_grenswaarde": {
  "note": "Netherlands: wettelijke grenswaarden (Arboregeling, bijlage XIII) — check the SER grenswaarden database (https://www.ser.nl/nl/thema/arbeidsomstandigheden/grenswaarden) for the current legal value; EU IOELVs are transposed into it."
 },
 "niosh_rel": {
  "twa_ppm": 35.0,
  "stel_or_ceiling_ppm": 200.0,
  "raw": "TWA 35 ppm (40 mg/m3) C 200 ppm (229 mg/m3)"
 },
 "osha_pel": "TWA 50 ppm (55 mg/m3) See Appendix G",
 "idlh_ppm": 1200.0,
 "idlh_raw": "1200 ppm",
 "gwp100": {
  "ar4": null,
  "ar6": null,
  "eu_fgas_2024_573_annex": null
 },
 "atmospheric_lifetime_years": null,
 "odp": 0,
 "gwp_note": null,
 "seveso_named": true,
 "health_effects": "Binds haemoglobin ~200× stronger than O₂ (COHb), starving tissues of oxygen. Odourless and colourless: headache and nausea at 100–200 ppm over hours, confusion and collapse above ~1000 ppm, death from ~1 % (10 000 ppm) within minutes. Flammable 11–75 vol%.",
 "main_toxic_effects_gestis": "Acute: \nDeficiency of oxygen in the body tissues as a consequence of partial inhibition of the transport of oxygen in the blood;\nin particular disturbance of the heart/circulatory system and neurological effects; metabolic disturbances\nChronic: \nditto at relatively high concentrations of long duration, performance deficits (psychosensorial, motor and mental) following repeated low exposure",
 "routes_of_exposure": "Main routes of exposure\nThe main intake pathway for carbon monoxide (CO) proceeds via the respiratory tract.\nRespiratory tract\nDue to its poor solubility in water, almost all CO in the inspired air reaches the alveoles and is very effectively absorbed through their membranes into the blood. The amount taken in is dependent on the partial pressure in the inspiration air and in the blood but also on a whole series of other factors, in particular the physical activity and on the duration of exposure as well as the extent of saturation of the hemoglobin reservoir achieved already.\nSkin\nNo data on the absorbability through intact skin is available.\nThis is probably less likely because even the epithelium of the upper airways is an effective barrier against the diffusion of CO.\nGastrointestinal tract\nNo data is available.\nUnder conditions encountered in practice, however, it is hardly conceivable that toxicologically-relevant amounts of CO can arrive at the gastrointestinal tract.",
 "ir_absorption_band_um": "4.6–4.7 µm (fundamental, 2143 cm⁻¹)",
 "monitoring": [
  "Electrochemical cells dominate workplace CO detection (ppm range); NDIR at 4.6 µm is used for flue-gas/CEMS and process % ranges where EC cells saturate or drift.",
  "Alarms typically 30 ppm (pre) / 60 ppm (main) for occupied areas; garages per EN 50545."
 ],
 "regulation_windows": [
  "IED 2024/1785 — CEMS on combustion plants (EN 14181 QAL)",
  "Workplace: EU IOELV 20 ppm / STEL 100 ppm (Dir. 2017/164/EU)",
  "EN 50291 (domestic) / EN 50545 (car parks) detector standards"
 ],
 "tremon_products": [
  "IR·OEM CO channel",
  "TRM-PGA process analyzer",
  "TRM-EX (EC or IR)"
 ],
 "sources": [
  "https://gestis-database.dguv.de/data?name=001110",
  "https://www.cdc.gov/niosh/npg/npgd0105.html",
  "https://pubchem.ncbi.nlm.nih.gov/compound/281",
  "IPCC AR6 WG1 Ch.7 Supplementary Material, Table 7.SM.7 (https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_Chapter07_SM.pdf)",
  "HITRAN/NIST IR band positions (approximate centre of the strongest band used for NDIR; https://hitran.org, https://webbook.nist.gov)"
 ]
}