PSI to kPa Converter

Converting US pressure ratings (psi) to SI metric (kPa) for international equipment specification, instrumentation, and code compliance.

Industrial process transmitters and gauges from Rosemount (Emerson), Endress+Hauser, Honeywell, Yokogawa, and ABB are configurable for either unit system — a pressure transmitter calibrated for 0–100 psi can be ranged equivalently for 0–689.5 kPa, and the HART or Foundation Fieldbus configuration must be in the local unit system to avoid operator confusion.

Pneumatic controller signals in legacy control systems are 3–15 psi per ISA S7.4 (US), while newer IEC 62734-compliant systems use 4–20 mA — converting the pneumatic signal range to kPa (the European equivalent for instrument air supply, typically 140 kPa or 20 psi) is required when maintaining both legacy and modern systems in the same plant.

Natural gas distribution pressures per US 49 CFR 192 are in psi (distribution mains typically 60–100 psi, service lines 0.25–60 psi) while the European equivalent EN 12007 specifies the same in bar or kPa (distribution 4–7 bar = 400–700 kPa, service 25–100 mbar = 2.5–10 kPa).

Compressed air system specifications in industrial plants differ: a 100 psi compressor in the US (about 7 bar, 690 kPa) is the standard shop air pressure, while European ISO 8573-1 specifies compressed air classes at 6, 8, 10, or 13 bar (600, 800, 1,000, or 1,300 kPa) — converting the US 100 psi to 690 kPa is required when reconciling pneumatic tool specifications across regions.

Hydraulic system working pressures in US mobile equipment (Caterpillar, John Deere, Case) are quoted in psi (3,000–5,000 psi for main hydraulics), while European OEM literature for the same class of equipment (Liebherr, Komatsu, JCB) is in bar or MPa — the conversion is required for fleet maintenance, parts ordering, and cross-regional equipment sharing.

Pressure testing of process piping and pressure vessels per ASME B31.3 or B31.1 in the US uses psi, while EN 13445 or PD 5500 in Europe uses bar or MPa — both are routine in international EPC projects where vessels and piping may be fabricated in one country and installed in another.

Fire sprinkler system working pressures per NFPA 13 are typically 175 psi (12 bar, 1,200 kPa) for light hazard, while European EN 12845 specifies the same in bar or kPa.

Hydraulic accumulator pre-charge pressures, gas cylinder test pressures (3,000 psi for oxygen, 2,640 psi for nitrogen, 2,215 psi for breathing air per CGA standards), and SCUBA tank ratings (3,000 psi or 200 bar) all require conversion when crossing unit system boundaries.

Medical gas pipeline pressures per NFPA 99 are in psi (50 psi medical air, 55 psi oxygen, 160 psi surgical air) while HTM 02-01 (UK) and DIN 13260 (Germany) specify the same in bar or kPa — the conversion is routine in hospitals that operate with international staff or equipment manufacturers.