Here is a list of spare parts available for the Crowcon Sensitron SMART 3G-D3 Gas Detector:
| Sensor Part Number | Description | Detector |
| KX155ME | METHANE detector, 4-20 mA, 0-100% LFL | S3515ME |
| KX155GP | LPG detector, 4-20 mA, 0-100% LFL | S2157GP |
| KX155BU | PROPANE detector, 4-20 mA, 0-100% LFL | S2157BU |
| KX155PR | BUTANE detector, 4-20 mA, 0-100% LFL | S2157PR |
| KX155VB | PETROL VAPOURS detector, 4-20 mA, 0-100% LFL | S2157VB |
| KX155H2 | HYDROGEN detector, 4-20 mA, 0-100% LFL | S2157H2 |
| KX624ME | METHANE detector, 4-20 mA, 0-100% LFL | S3916ME |
| KX654PR | PROPANE detector, 4-20 mA, 0-100% LFL | S2602PR |
| KX654BU | BUTANE detector, 4-20 mA, 0-100% LFL | S2602BU |
| KX654GP | LPG detector, 4-20 mA, 0-100% LFL | S2602GP |
| K4433R454B | R454B detector, 4-20 mA, 0-100% LFL | S4435R454B |
| K4827R454C | R454C detector, 4-20mA, 0-100% LFL | S4829R454C |
| K3425R32 | R32 DIFLUOROMETHANE detector, 4-20 mA, 0-100% LFL | S3427R32 |
| K3429R1234YF | R1234yf detector, 4-20 mA, 0-100% LFL | S3431R1234YF |
| K3433R1234ZE | R1234ze detector, 4-20 mA, 0-100% LFL | S3436R1234ZE |
| KX641O2 | OXYGEN (O2) detector, 0-25% Vol., 4-20 mA | S2643O2 |
| KX131CO | CARBON MONOXIDE (CO) detector, 0-500 ppm, 4-20 mA | S2163CO |
| KX225AM | AMMONIA (NH3) detector, 0-100 ppm, 4-20 mA | S3227AM |
| KX133AM | AMMONIA (NH3) detector, 0-200 ppm, 4-20 mA | S2165AM |
| KX135AM | AMMONIA (NH3) detector, 0-1000 ppm, 4-20 mA | S2167AM |
| K3229AM | AMMONIA (NH3) detector, 0-5000 ppm, 4-20 mA | S3231AM |
| KX137HS | HYDROGEN SULPHIDE (H2S) detector, 0-50 ppm, 4-20 mA | S2169HS |
| KX145NO | NITRIC OXIDE (NO), 0-100 ppm, 4-20 mA | S2177NO |
| K3593H2 | HYDROGEN (H2) detector, 0-2000 ppm, 4-20 mA | S3313H2 |
| K4547H2 | HYDROGEN (H2) detector, 0-3000 ppm, 4-20 mA | S3395H2 |
| KX651CO2 | CARBON DIOXIDE (CO2) detector, 0-2% Vol., 4-20 mA | S2634CO2 |
| KX652CO2 | CARBON DIOXIDE (CO2) detector, 0-5% Vol., 4-20 mA | S2635CO2 |
| KX445CO2 | CARBON DIOXIDE (CO2) detector, 0-30% Vol., 4-20 mA | S2449CO2 |
| KX444CO2 | CARBON DIOXIDE (CO2) detector, 0-5000 ppm, 4-20 mA | S3763CO2 |
| KX630CO2 | CARBON DIOXIDE (CO2) detector, 0-100% Vol., 4-20 mA | S2636CO2 |
| KX944R32 | R32 detector, 0-2000 ppm, 4-20 mA | S3943R32 |
| K3596R134A | R134a detector, 0-2000 ppm, 4-20 mA | S3163R134A |
| K3599SF6 | SF6 detector, 0-2000 ppm, 4-20 mA | S3601SF6 |
| K3656R125 | R125 detector, 0-2000 ppm, 4-20 mA | S3661R125 |
| K3657R1234YF | R1234yf detector, 0-2000 ppm, 4-20 mA | S3662R1234YF |
| K3948R1234ZE | R1234ze detector, 0-2000 ppm, 4-20 mA | S3949R1234ZE |
| K3658R404A | R404A detector, 0-2000 ppm, 4-20 mA | S3663R404A |
| K3659R407A | R407A detector, 0-2000 ppm, 4-20 mA | S3917R407A |
| K3920R407F | R407F detector, 0-2000 ppm, 4-20 mA | S3664R407F |
| K3923R449A | R449 detector, 0-2000 ppm, 4-20 mA | S3924R449A |
| K3660R507A | R507A detector, 0-2000 ppm, 4-20 mA | S3665R507A |
| K3017R410A | R410A detector, 0-2000 ppm, 4-20 mA | S3673R410A |
| K3952R417A | R417A detector, 0-2000 ppm, 4-20 mA | S3953R417A |
| K3956R448 | R448 detector, 0-2000 ppm, 4-20 mA | S3957R448 |