Reid Vapor Pressure Calculator
Calculate RVP and True Vapor Pressure (TVP) for petroleum products
Input Parameters
Enter RVP or product data for TVP calculation
Vapor Pressure Results
Enter data and click Calculate
RVP Regulations
- Summer (Jun-Sep): 9.0 psi max (7.8 in ozone areas)
- RFG Areas: 7.0-7.8 psi
- California: 7.0 psi (CARB)
- Winter: Up to 15.0 psi allowed
Formula Reference
RVP to TVP Conversion (EPA AP-42)
True Vapor Pressure (TVP) at temperature T:
For Gasoline:
TVP = exp(A - B/(T + 460))
Where:
A = 15.64 - 1.854 * S^0.5 - 0.8742 * S
B = 8742 - 1042 * S^0.5 - 599.2 * S
S = RVP / 14.7 (dimensionless)
T = Storage temperature (F)
Simplified correlation:
TVP (psi) = RVP * exp(0.0266 * (T - 100))
Blend RVP Calculation
Ethyl's Blending Index Method:
RVP_blend^1.25 = Sum(xi * RVPi^1.25)
Where:
xi = volume fraction of component i
RVPi = RVP of component i (psi)
Rearranged:
RVP_blend = (Sum(xi * RVPi^1.25))^0.8
Common Component RVP Values
| Component | RVP (psi) | Notes |
|---|---|---|
| n-Butane | 52 | Major blending component |
| Isobutane | 72 | Alkylation feed |
| Pentanes | 15 | Natural gasoline |
| Reformate | 3-5 | Low RVP |
| FCC Gasoline | 4-6 | Medium RVP |
| Alkylate | 4-5 | Low RVP, high octane |
| Ethanol | 2.3 | But increases blend RVP! |