R-290 (propane) · C3H8
R-290 (Propane, CAS 74-98-6) is a single-component refrigerant; this page gives its saturation pressure and saturated liquid and vapour densities from -40 to 60 °C.
Saturation pressure and saturated liquid and vapour densities are computed from CoolProp==6.6.0 - reference Helmholtz equation of state for Propane and tabulated over -40–60 °C.
- Also known as
- Propane, HC-290, R290, n-propane
- CAS number
- 74-98-6
- Tabulated range
- -40–60 °C · saturation line
- Refrigerant
- R-290
- Chemical name
- Propane
- GWP (100-yr)
- 3.3
- ASHRAE 34 class
- A3
GWP 3.3 — IPCC Fourth Assessment Report (AR4, 2007), 100-year GWP. U.S. EPA - Technology Transitions GWP Reference Table. U.S. Environmental Protection Agency, Technology Transitions GWP Reference Table: propane (R-290) 100-year GWP = 3.3 (basis IPCC 2007 / AR4). https://www.epa.gov/climate-hfcs-reduction/technology-transitions-gwp-reference-table
ASHRAE 34 A3 — ANSI/ASHRAE Standard 34 safety group classification. ANSI/ASHRAE Standard 34 - Designation and Safety Classification of Refrigerants. ANSI/ASHRAE Standard 34-2022, Designation and Safety Classification of Refrigerants: R-290 (propane) assigned safety group A3.
- Saturation pressure
- 9.521bar
- Pressure
- 952.1kPa
- Gauge
- 123.4psig
- Liquid density
- 492.4kg/m³
- Vapour density
- 20.62kg/m³
Read the saturation line either way
Set a temperature to read its saturation pressure and densities, or set a pressure to read the saturation temperature. Every number is interpolated from the committed table below and clamped to the validated -40–60 °C range — nothing is computed from a property model in your browser.
Values are interpolated along the tabulated saturation line below — both the temperature and the pressure stay within the validated -40–60 °C range and are never extrapolated.
- Saturation temp
- 25.0 °C
- Saturation pressure
- 9.521 bar
- Pressure
- 952.1 kPa
- Gauge pressure
- 123.4 psig
- Liquid density
- 492.4 kg/m³
- Vapour density
- 20.62 kg/m³
Every tabulated point
Saturation pressure (absolute, shown in kPa and bar, with the gauge value in psig at standard atmosphere) and the saturated liquid and vapour densities at each temperature. A negative psig is a partial vacuum below one atmosphere.
| T °C | p kPa | p bar | p psig | ρ liq kg/m³ | ρ vap kg/m³ |
|---|---|---|---|---|---|
| -40 | 111.1 | 1.111 | 1.4 | 578.4 | 2.63 |
| -35 | 137.2 | 1.372 | 5.2 | 572.6 | 3.20 |
| -30 | 167.8 | 1.678 | 9.6 | 566.6 | 3.87 |
| -25 | 203.4 | 2.034 | 14.8 | 560.6 | 4.63 |
| -20 | 244.5 | 2.445 | 20.8 | 554.5 | 5.50 |
| -15 | 291.6 | 2.916 | 27.6 | 548.2 | 6.50 |
| -10 | 345.3 | 3.453 | 35.4 | 541.8 | 7.63 |
| -5 | 406.0 | 4.060 | 44.2 | 535.3 | 8.91 |
| 0 | 474.5 | 4.745 | 54.1 | 528.6 | 10.35 |
| 5 | 551.1 | 5.511 | 65.2 | 521.8 | 11.97 |
| 10 | 636.6 | 6.366 | 77.6 | 514.7 | 13.78 |
| 15 | 731.5 | 7.315 | 91.4 | 507.5 | 15.81 |
| 20 | 836.5 | 8.365 | 106.6 | 500.1 | 18.08 |
| 25 | 952.1 | 9.521 | 123.4 | 492.4 | 20.62 |
| 30 | 1079.0 | 10.790 | 141.8 | 484.4 | 23.45 |
| 35 | 1217.9 | 12.179 | 161.9 | 476.1 | 26.62 |
| 40 | 1369.4 | 13.694 | 183.9 | 467.5 | 30.16 |
| 45 | 1534.3 | 15.343 | 207.8 | 458.4 | 34.15 |
| 50 | 1713.3 | 17.133 | 233.8 | 448.9 | 38.63 |
| 55 | 1907.2 | 19.072 | 261.9 | 438.8 | 43.71 |
| 60 | 2116.8 | 21.168 | 292.3 | 428.0 | 49.49 |
R-290 saturation pressure at a glance
At -20 °C, R-290 saturation pressure is about 2.45 bar (245 kPa; 20.8 psig). At 0 °C, R-290 saturation pressure is about 4.74 bar (474 kPa; 54.1 psig). At 25 °C, R-290 saturation pressure is about 9.52 bar (952 kPa; 123.4 psig). At 40 °C, R-290 saturation pressure is about 13.69 bar (1369 kPa; 183.9 psig).
Where the numbers come from
Every value on this page is computed by a deterministic equation of state — none is entered by hand. The generating method and the references it is checked against:
- ▸NIST Chemistry WebBook, SRD 69 - Thermophysical Properties of Fluid Systems (REFPROP-derived saturation tables), propane (CAS 74-98-6)
- ▸CoolProp 6.6.0 - reference Helmholtz equation of state for propane (Lemmon, McLinden & Wagner, 2009)
- ▸U.S. EPA - Technology Transitions GWP Reference Table (100-year GWP, IPCC AR4 basis)
- ▸ANSI/ASHRAE Standard 34-2022 - Designation and Safety Classification of Refrigerants
Model: CoolProp==6.6.0 - reference Helmholtz equation of state for Propane · Generated 2026-06-07
The committed data file for this page is published as JSON on GitHub under CC BY 4.0.
Checked against cited values
The equation of state is cross-checked against independently cited saturation points. The page is published only because every check passes.
| Property / point | Saturation pressure · 25 °C |
| Cited reference value | 952.07 kPa |
| Model computed | 952.07 kPa |
| Error vs reference | 0% (tolerance 1%) |
NIST Chemistry WebBook, SRD 69 - Thermophysical Properties of Fluid Systems. NIST Chemistry WebBook, SRD 69, Thermophysical Properties of Fluid Systems, propane (R-290, CAS 74-98-6), saturation curve at 25 degC: saturation pressure = 952.07 kPa. https://webbook.nist.gov/cgi/fluid.cgi?ID=C74986&Action=Page
| Property / point | Saturated liquid density · 25 °C |
| Cited reference value | 492.36 kg/m3 |
| Model computed | 492.36 kg/m3 |
| Error vs reference | 0.001% (tolerance 1%) |
NIST Chemistry WebBook, SRD 69 - Thermophysical Properties of Fluid Systems. NIST Chemistry WebBook, SRD 69, Thermophysical Properties of Fluid Systems, propane (R-290, CAS 74-98-6), saturation curve at 25 degC: saturated liquid density = 492.36 kg/m3. https://webbook.nist.gov/cgi/fluid.cgi?ID=C74986&Action=Page
Before you use these numbers
- ▸CoolProp reference Helmholtz equation of state (Lemmon, McLinden & Wagner, 2009) for propane. Saturation properties only, tabulated from -40 to +60 degC; superheated and single-phase data are out of scope for this page. The critical point is 96.74 degC / 4251.2 kPa, well above the table top, so every tabulated state is sub-critical. Values are for preliminary design; verify against vendor data for critical service.
- ▸Saturation properties only — these are two-phase (saturation-line) values; superheated and sub-cooled single-phase data are out of scope for this page. The critical point is 96.74 °C / 4251.2 kPa, above the tabulated range.
- ▸Values are tabulated only inside the -40–60 °C range shown; the equation of state is not extrapolated beyond it here.
- ▸Use for preliminary design; verify for critical service.
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