{
 "license": "CC BY 4.0 — Tremon Solutions, https://www.tremon.nl/gases/n2o",
 "generated": "2026-09-17",
 "key": "n2o",
 "name": "Nitrous oxide",
 "formula": "N₂O",
 "formula_plain": "N2O",
 "iupac": "nitrous oxide",
 "synonyms": [
  "Dinitrogen monoxide",
  "Hyponitrous acid anhydride",
  "Laughing gas"
 ],
 "cas": "10024-97-2",
 "ec_number": "233-032-0",
 "un_number": "1070",
 "un_shipping_name": "Nitrous oxide",
 "transport_class": "2.2 (Non-flammable, non-toxic gases)",
 "pubchem_cid": 948,
 "molar_mass_g_mol": 44.01,
 "mg_m3_per_ppm_20c": 1.83,
 "boiling_point_c": -88.5,
 "sublimation_point_c": null,
 "melting_point_c": -90.8,
 "critical_temp_c": 36.4,
 "critical_pressure_bar": 72.45,
 "vapour_pressure_bar": 50.8,
 "vapour_pressure_at_c": 20.0,
 "density_gas_kg_m3": 1.9781,
 "density_condition": "0 °C, 1013 mbar",
 "relative_density_air": 1.53,
 "solubility_water": "1,5 g/l at 15 °C",
 "appearance": "gas liquefied under pressure, colourless, sweetish odour",
 "odour": "sweetish odour",
 "chemical_character": [
  "Oxidizing gas.",
  "The substance itself does not burn, but in contact with combustible substances it increases the risk of fire and can fuel any existing fire substantially.",
  "Like oxygen, nitrous oxide maintains a fire involving combustible material like wood or sulfur.",
  "Only slightly soluble in water.",
  "Gas is heavier than air.",
  "Acute or chronic health hazards result from the substance."
 ],
 "hazard_class": "oxidizer; anaesthetic (toxic at chronic low ppm); greenhouse gas",
 "ghs_classification": [
  "Oxidising gases, Category 1; H270",
  "Gases under pressure, liquefied gas; H280",
  "Specific Target Organ Toxicity (single exposure), Category 3; H336",
  "Reproductive toxicity, Category 1B; H360Df",
  "Specific Target Organ Toxicity (repeated exposure), Category 1; H372",
  "Hazardous to the ozone layer, Category 1; H420"
 ],
 "ghs_signal_word": "Danger",
 "ghs_hazard_statements": [
  "H270: May cause or intensify fire; oxidiser.",
  "H280: Contains gas under pressure; may explode if heated.",
  "H336: May cause drowsiness or dizziness.",
  "H360Df: May damage the unborn child. Suspected of damaging fertility.",
  "H372: Causes damage to organs through prolonged or repeated exposure.",
  "H420: Harms public health and the environment by destroying ozone in the upperatmosphere"
 ],
 "euh_statements": [],
 "nfpa704": {
  "health": 2,
  "flammability": 0,
  "instability": 0,
  "special": "OX"
 },
 "lel_vol_pct": null,
 "uel_vol_pct": null,
 "autoignition_c": null,
 "temperature_class": null,
 "explosion_group": null,
 "eu_ioelv": {
  "twa_8h_ppm": null,
  "twa_8h_mg_m3": null,
  "stel_15min_ppm": null,
  "stel_15min_mg_m3": null,
  "directive": null
 },
 "de_agw": {
  "twa_ppm": 100.0,
  "twa_mg_m3": 180.0,
  "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": 25.0,
  "stel_or_ceiling_ppm": null,
  "raw": "TWA 25 ppm (46 mg/m3) (TWA over the time exposed) [*Note: REL for exposure to waste anesthetic gas.]"
 },
 "osha_pel": "none",
 "idlh_ppm": null,
 "idlh_raw": "N.D.",
 "gwp100": {
  "ar4": 298,
  "ar6": 273,
  "eu_fgas_2024_573_annex": 273
 },
 "atmospheric_lifetime_years": 109,
 "odp": null,
 "gwp_note": "ODP: N₂O is the dominant ozone-depleting emission of the 21st century (Ravishankara et al. 2009) but has no Montreal-Protocol ODP value assigned.",
 "seveso_named": true,
 "health_effects": "Anaesthetic gas. Acute: euphoria, dizziness, loss of coordination; high concentrations asphyxiate. Chronic low-level exposure (waste anaesthetic gas) inactivates vitamin B₁₂ → neuropathy, and is linked to reproductive effects — hence the 100 ppm (DE) / 25 ppm (NIOSH) limits.",
 "main_toxic_effects_gestis": "Acute: \nnervous system dysfunction (analgaesic and narcotic effects at high concentrations), haematopoiesis dysfunction (via deactivation of vitamin B12) .\nChronic: \nimpairment of blood formation, disturbance and damage to the nervous system (neuromyelopathies) [7619, 7748].",
 "routes_of_exposure": "Main routes of exposure\nThe main route of exposure for nitrous oxide (N2O) is via the respiratory tract. [7748, 7619]\nRespiratory tract\nApproximately 5 % of inhaled N2O is absorbed into the body. Absorption is particular rapid at the onset of exposure: inhalation of an atmosphere containing 80 % N2O resulted in an uptake of approximately 1 l/min during the first 1 - 2 min. The subsequent decline was inversely proportional to the square root of the exposure time until a state of equilibrium was reached. [7619, 8093]\nSkin\nAs a small quantity of N2O is eliminated unchanged via the skin (see \"metabolism\"), it must be assumed that the gas is capable of penetrating the skin. However, systemic uptake of N2O through the skin is physicochemically limited due to its low solubility in the blood. This is generally considered to be negligible. [7619, 99999]\nGastrointestinal tract\nAbsorption of the gas via the digestive tract is not practically relevant; no information is available on this absorption pathway. \nExperience from using N2O as an anaesthetic gas has, if anything, revealed the reverse process: N2O dissolved in the blood can diffuse into the intestine, potentially causing problems due to inflation (similar to other body cavities).",
 "ir_absorption_band_um": "4.5 µm (ν₃, 2224 cm⁻¹); 7.8 µm (ν₁, 1285 cm⁻¹)",
 "monitoring": [
  "NDIR at 4.5 µm (with CO₂ cross-compensation) for hospital/dental waste-gas monitoring and for process/CEMS (N₂O is an IED and ETS-reported pollutant).",
  "Alarm/limit: 100 ppm AGW (DE) / 25 ppm NIOSH TWA for anaesthetic use; agriculture and nitric-acid plants report N₂O under IED/ETS."
 ],
 "regulation_windows": [
  "IED 2024/1785 — N₂O is a reported pollutant (nitric/adipic acid, waste incineration)",
  "EU ETS — N₂O from nitric acid plants",
  "Workplace: DE AGW 100 ppm; NIOSH REL 25 ppm (anaesthetic waste gas)"
 ],
 "tremon_products": [
  "IR·OEM N₂O channel",
  "TRM-PGA process analyzer"
 ],
 "sources": [
  "https://gestis-database.dguv.de/data?name=004230",
  "https://www.cdc.gov/niosh/npg/npgd0465.html",
  "https://pubchem.ncbi.nlm.nih.gov/compound/948",
  "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)",
  "IPCC AR4 WG1 Ch.2, Table 2.14 (https://www.ipcc.ch/site/assets/uploads/2018/02/ar4-wg1-chapter2-1.pdf)",
  "Regulation (EU) 2024/573, Annex I/III (https://eur-lex.europa.eu/eli/reg/2024/573/oj)",
  "HITRAN/NIST IR band positions (approximate centre of the strongest band used for NDIR; https://hitran.org, https://webbook.nist.gov)"
 ]
}