Gas Detection Sensors
Sensidyne plug-in gas detection sensors are available for a wide array of applications in many industries. Advanced intelligent sensors manufactured by Sensidyne, and from selected suppliers are available for detecting toxic and combustible gases as well as oxygen deficiency or enrichment.
Intelligent Sensidyne sensors contain non-volatile memory for gas name or type, span, measuring units, alarm levels, the latest zero and span calibration data, compensation tables, remaining sensor life, factory codes and history, time and date stamp, as applicable.
SensAlert & SensAlert Plus Sensor Data Table
| SensAlert P/N | SensAlert PLUS P/N | TARGET GAS OR VAPOR | GAS DATA1, 2 | SENSOR | ToD | Response Time | ENVIRONMENTAL9 | ||||||
| Formula | Density | TLV-TWA | IDLH | Span4-Units | Type1, 3 | Cell8 | T506 | T906 | Temp. F | Humidity | |||
| 011243-D-3X | 823-0201-22 FM | Ammonia | NH3 | 0.6 | 25 ppm | 300 ppm | 50 ppm | EC-LI, D3 | n/a | 11 | 70 | -4° to 122o | 15-90% RH |
| 011243-D-1 | 823-0201-21 FM | Ammonia | NH3 | 0.6 | 25 ppm | 300 ppm | 100 ppm | EC-LI, D | n/a | 11 | 70 | -4° to 122o | 15-90% RH |
| 011243-D-2 | 823-0201-41 | Ammonia | NH3 | 0.6 | 25 ppm | 300 ppm | 300 ppm | EC-LI, D | n/a | 15 | 90 | -4° to 122o | 10-90% RH |
| 011343-D-1 | 823-0201-42 | Ammonia | NH3 | 0.6 | 25 ppm | 300 ppm | 500 ppm | EC-LI, D | n/a | 20 | 90 | -4° to 122o | 10-90% RH |
| n/a | 823-0249-51 | Acetylene IR | C2H2 | 0.9 | Asphyxiate | - - | 50% LEL | Infrared | n/a | 10 | 30 | -30° to131° | 5-95% RH |
| 121042-D-1 | Pending | Arsine | AsH3 | 2.7 | 0.05 ppm | 3 ppm | 1.00 ppm | EC, ND3 | n/a | 50 | 90 | -4° to 122o | 5-95% RH |
| Use Chlorine | Use Chlorine | Bromine | Br2 | 5.5 | 3.0 ppm | 3 ppm | 10 ppm | EC, D | n/a | - - | - - | -4° to 122o | 5-95% RH |
| n/a | 823-0205-51 | Carbon Dioxide IR | CO2 | 1.5 | 0.50% | 3.00% | 5.00% Vol. | Infrared | n/a | 65 | 105 | -4° to 131o | 0-95% RH |
| 195272-D-1 | 823-0219-23 FM | Carbon Monoxide | CO | 0.94 | 25 ppm | 1,200 ppm | 100 ppm | EC, ND | n/a | 10 | 30 | -4° to 122o | 15-90% RH |
| 195272-D-4 | Pending | Carbon Monoxide | CO | 0.94 | 25 ppm | 1,200 ppm | 300 ppm | EC, ND | n/a | 10 | 30 | -4° to 122o | 15-90% RH |
| 195272-D-2 | 823-0219-22 FM | Carbon Monoxide | CO | 0.94 | 25 ppm | 1,200 ppm | 500 ppm | EC, ND | n/a | 10 | 30 | -4° to 122o | 15-90% RH |
| 195272-D-3X | Pending | Carbon Monoxide | CO | 0.94 | 25 ppm | 1,200 ppm | 1000 ppm | EC, ND | n/a | 10 | 30 | -4° to 122o | 5-95% RH |
| 198262-D-1 | 823-0219-41 | Carbon Monoxide | CO | 0.94 | 25 ppm | 1,200 ppm | 100 ppm | EC-LI, ND | n/a | 10 | 30 | -4° to 122o | 15-90% RH |
| 198262-D-2 | 823-0219-42 | Carbon Monoxide | CO | 0.94 | 25 ppm | 1,200 ppm | 500 ppm | EC-LI, ND | n/a | 10 | 30 | -4° to 122o | 15-90% RH |
| 025142-D-2 | 823-0202-22 FM | Chlorine | Cl2 | 2.5 | 0.5 ppm | 10 ppm | 5.00 ppm | EC, ND | C | 10 | 40 | -4° to 122o | 15-90% RH |
| 025142-D-1 | 823-0202-21 FM | Chlorine | Cl2 | 2.5 | 0.5 ppm | 10 ppm | 10.0 ppm | EC, ND | C | 10 | 40 | -4° to 122o | 15-90% RH |
| n/a | 823-0202-23 | Chlorine | Cl2 | 2.5 | 0.5 ppm | 10 ppm | 20.0 ppm | EC, ND | C | 10 | 30 | -4° to 122o | 15-95% RH |
| 021232-D-3 | Pending | Chlorine | Cl2 | 2.5 | 0.5 ppm | 10 ppm | 100 ppm | EC, ND | n/a | 18 | 60 | -4° to 122o | 5-95% RH |
| 021201-D-1 | n/a | Chlorine | Cl2 | 2.5 | 0.5 ppm | 10 ppm | 10.0 ppm | Refillable EC | n/a | 60 | 120 | 23° to 113o | 5-95% RH |
| 391132-D-1 | 823-0239-21 | Chlorine Dioxide | ClO2 | 2.3 | 0.1 ppm | 5 ppm | 1.00 ppm | EC, ND | C | 20 | 120 | -4° to 122o | 15-90% RH |
| 111250-D-1 | 823-0211-31 FM | Combustibles, General | - - | - - | Asphixiate | - - | 100% LEL | Catalytic | n/a | T-60: <12 sec | -40° to167° | 5-95% RH | |
| 111253-D-1 | 823-0211-32 | Comb. H2, ETO, Acetylene | - - | - - | Asphixiate | - - | 100% LEL | Catalytic | n/a | T-60: <5 sec | -4° to122° | 5-95% RH | |
| 101236-D-1 | 823-0210-41 | Hydrogen Specific LEL | H2 | 0.07 | Asphixiate | - - | 100% LEL | EC, ND | n/a | 20 | 70 | -4° to 122o | 15-90% RH |
| n/a | 823-0211-51 FM | Combustibles IR | Hydrocarbons | Asphixiate | - - | 100% LEL | Infrared | n/a | T-60: <12 sec | -13° to 167o | 0-99% RH | ||
| 491255-D-1 | 823-0249-51 | Combustibles IR Acetylene | C2H2 | 0.9 | 2,500 ppm | - - | 50% LEL | Infrared | n/a | 10 | 30 | -4° to 122o | 5-95% RH |
| 291042-D-1 | Pending | Diborane | B2H6 | 2.9 | 0.1 ppm | 15 ppm | 1.00 ppm | EC, ND | n/a | 45 | 100 | -4° to 122o | 5-95% RH |
| c/f | Pending | Dichlorosilane | SiH2Cl2 | 1.3 | 5 ppm | - - | 10.0 ppm | EC, ND | n/a | 30 | 90 | -4° to 122o | 5-95% RH |
| 452132-D-1 | 823-0245-21 | Ethylene Oxide (ETO) | C2H4O | 1.5 | 1 ppm | 800 ppm | 10.0 ppm | EC, ND | n/a | 15 | 60 | -4° to 104o | 15-95% RH |
| 151142-D-1X | 823-0215-21 | Fluorine | F2 | 1.3 | 0.1 ppm | 25 ppm | 10.0 ppm | EC, ND | n/a | 10 | 30 | -4° to 122o | 5-95% RH |
| 151142-D-2X | 823-0215-22 | Fluorine | F2 | 1.3 | 0.1 ppm | 25 ppm | 25.0 ppm | EC, ND | n/a | 10 | 30 | -4° to 122o | 5-95% RH |
| 302042-D-1 | Pending | Germane | GeH4 | 2.7 | 0.2 ppm | - - | 2.00 ppm | EC, ND | n/a | 10 | 30 | -4° to 122o | 5-95% RH |
| 481042-D-1X | Pending | Hydrazine | N2H4 | 1.1 | 0.01 ppm | 50 ppm | 1.00 ppm | EC, ND | n/a | 30 | 120 | -4° to 122o | 5-95% RH |
| 101332-D-1 | 823-0210-21 FM | Hydrogen Specific PPM | H2 | 0.07 | Asphixiate | - - | 1000 ppm | EC, ND | n/a | 20 | 70 | -4° to 122o | 15-90% RH |
| 101236-D-1 | 823-0210-41 | Hydrogen Specific LEL | H2 | 0.07 | Asphixiate | - - | 100% LEL | EC, ND | n/a | 40 | 120 | -4° to 122o | 15-90% RH |
| Use HCl | Use HCl | Hydrogen Bromide | HBr | 2.8 | 3 ppm | 30 ppm | 10.0 ppm | EC, ND | n/a | 45 | 120 | -4° to 122o | 5-95% RH |
| 083142-D-3X | 823-0208-21 FM | Hydrogen Chloride | HCl | 1.3 | 2 ppm | 50 ppm | 10.0 ppm | EC, ND | S | 15 | 30 | -4° to 122o | 15-90% RH |
| 083142-D-1 | 823-0208-22 FM | Hydrogen Chloride | HCl | 1.3 | 2 ppm | 50 ppm | 20.0 ppm | EC, ND | S | 15 | 30 | -4° to 122o | 15-90% RH |
| 081201-D-1 | n/a | Hydrogen Chloride | HCl | 2.3 | 2 ppm | 50 ppm | 10.0 ppm | Refillable EC | n/a | 40 | 180 | 23° to 104o | 5-95% RH |
| 081232-D-2 | Pending | Hydrogen Chloride | HCl | 2.3 | 2 ppm | 50 ppm | 100 ppm | EC, ND | n/a | 36 | 120 | -4° to 122o | 5-95% RH |
| 033142-D-1 | 823-0203-21 | Hydrogen Cyanide | HCN | 0.9 | 4.7 ppm | 50 ppm | 20.0 ppm | EC, D3 | n/a | 10 | 30 | -4° to 122o | 15-95% RH |
| 031232-D-2X | Pending | Hydrogen Cyanide | HCN | 0.9 | 4.7 ppm | 50 ppm | 100 ppm | EC, D | n/a | 45 | 150 | -4° to 122o | 5-95% RH |
| 071142-D-1 | 823-0207-21 FM | Hydrogen Fluoride | HF | 0.7 | 0.5 ppm | 30 ppm | 10.0 ppm | EC, D | C | 15 | 45 | -4° to 122o | 15-90% RH |
| 071142-D-2X | 823-0207-22 FM | Hydrogen Fluoride | HF | 0.7 | 0.5 ppm | 30 ppm | 20.0 ppm | EC, D | C | 15 | 45 | -4° to 122o | 15-90% RH |
| 071201-D-1 | n/a | Hydrogen Fluoride | HF | 0.7 | 0.5 ppm | 30 ppm | 10.0 ppm | Refillable EC | n/a | 60 | 300 | 23° to 104o | 5-95% RH |
| 062272-D-1 | 823-0206-22 FM | Hydrogen Sulfide | H2S | 1.2 | 10 ppm | 100 ppm | 50 ppm | EC, ND | S | 10 | 30 | -40o to 122° | 15-90% RH |
| 062272-D-2 | 823-0206-21 FM | Hydrogen Sulfide | H2S | 1.2 | 10 ppm | 100 ppm | 100 ppm | EC, ND | S | 10 | 30 | -40o to 122° | 15-90% RH |
| 421232-D-1 | 823-0242-21 | Nitric Oxide | NO | 1 | 25 ppm | 100 ppm | 100 ppm | EC, ND | n/a | 5 | 15 | -4° to 122o | 5-95% RH |
| 211232-D-1 | 823-0221-21 | Nitrogen Dioxide | NO2 | 1.6 | 3 ppm | 20 ppm | 10.0 ppm | EC, ND | n/a | 15 | 40 | -4° to 122o | 15-90% RH |
| 403162-D-1 | 823-0240-41 FM | Oxygen | O2 | 1.13 | <19.5% | <18% | 25.0%Vol | EC, D | n/a | 4 | 10 | -4° to 122o | 15-90% RH |
| 403162-D-2X | n/a | Oxygen, Process | O2 | 1.13 | - - | - - | 10.0%Vol | EC, D | n/a | 4 | 10 | -4° to 122o | 5-95% RH |
| 403162-D-3X | n/a | Oxygen, Process | O2 | 1.13 | - - | - - | 25.0%Vol | EC, D | n/a | 4 | 10 | -4° to 122o | 5-95% RH |
| 403172-D-3 | n/a | Oxygen, Membrane | O2 | 1.13 | <19.5% | <18% | 25.0%Vol | EC, D | n/a | - - | <10 | 50° to 104o | 5-95% RH |
| 432032-D-1 | Pending | Ozone | O3 | 1.6 | 0.1 ppm | 5 ppm | 2.00 ppm | EC, ND | n/a | 45 | 150 | -4° to 122o | 5-95% RH |
| 471042-D-1X | 823-0247-21 | Phosgene | COCl2 | 3.4 | 0.1 ppm | 2 ppm | 1.00 ppm | EC, ND | n/a | 60 | 120 | -4° to 122o | 15-90% RH |
| 131042-D-1 | Pending | Phosphine | PH3 | 1.2 | 0.3 ppm | 50 ppm | 1.00 ppm | EC, ND | n/a | 10 | 30 | -4° to 122o | 5-95% RH |
| 145142-D-1 | Pending | Silane | SiH4 | 1.3 | 5 ppm | - - | 10.0 ppm | EC, ND | n/a | 30 | 90 | -4° to 122o | 5-95% RH |
| 462273-D-1X | Pending | Styrene | C8H8 | 3.6 | 20 ppm | 700 ppm | 200 ppm | EC, ND | n/a | 25 | 75 | -4° to 122o | 5-95% RH |
| n/a | 823-0218-22 FM | Sulfur Dioxide, H2S Filtered | SO2 | 2.3 | 2 ppm | 100 ppm | 10.0 ppm | EC, ND | n/a | 10 | 15 | -4° to 122o | 15-90% RH |
| 182132-D-3X | n/a | Sulfur Dioxide | SO2 | 2.3 | 2 ppm | 100 ppm | 10.0 ppm | EC, ND | n/a | 10 | 15 | -4° to 122o | 5-95% RH |
| 182132-D-1 | n/a | Sulfur Dioxide | SO2 | 2.3 | 2 ppm | 100 ppm | 20.0 ppm | EC, ND | n/a | 5 | 15 | -4° to 122o | 5-95% RH |
| 181233-D-1 | 823-0218-21 FM | Sulfur Dioxide, H2S Filtered | SO2 | 2.3 | 2 ppm | 100 ppm | 20.0 ppm | EC, ND | n/a | 10 | 15 | -4° to 122o | 15-90% RH |
| 181233-D-2 | Pending | Sulfur Dioxide, H2S Filtered | SO2 | 2.3 | 2 ppm | 100 ppm | 100 ppm | EC, ND | n/a | 5 | 20 | -4° to 122o | 15-90% RH |
| 181201-D-1X | n/a | Sulfur Dioxide | SO2 | 2.3 | 2 ppm | 100 ppm | 10.0 ppm | Refillable EC | n/a | 40 | 240 | 23° to 104o | 15-90% RH |
| SensAlert P/N | SensAlert PLUS P/N | TARGET GAS OR VAPOR | Formula | Density | TLV-TWA | IDLH | Span4-Units | Type1, 3 | Cell8 | T506 | T906 | Temp. F | Humidity |
| GAS DATA1, 2 | SENSOR | ToD | Response Time | ENVIRONMENTAL9 | |||||||||
1 Refillable means membrane and electrolyte are renewable, <: Less than or equal to, >: Greater than or equal to, n/a: not available.
2 Gas Data are from ACGIH (TLV-TWA) and NIOSH (IDLH) but may be noted as Ceiling or STEL. The user is responsible for verifying table data.
3 D: Sensor life is directly proportional to target gas exposure. ND: Sensor is not depleted by exposure to target gas and life is expected to be more than 2 years.
4 Lower Detection Limit is 3% of Span plus one digit (SensAlert) and 3% of span (PLUS). Number of zeros indicates sensor and display resolution.
7 LCD is the SensAlert gas type or name displayed. PLUS spells out the gas name or type.
8 ToD is the Test-on-Demand cell option and type designation for SensAlert PLUS only.
9 PLUS Temperature / Humidity specs given. Short term (hours) temperature / humidity excursions acceptable.
Sensor Technologies
Electrochemical Sensors
Electrochemical sensors are primarily used to detect toxic gases and oxygen. Toxic gases are detected in parts per million (PPM) while oxygen is measured in percent by volume (%Vol). Electrochemical sensors contain electrodes immersed in electrolyte inside a housing with a porous hydrophobic membrane. When the gas diffuses through the membrane into the electrolyte it produces a small but repeatable electrical current proportional to the gas concentration.
Catalytic Bead Sensors
Catalytic bead combustible sensors have been used since the 1930s. They consist of tiny heated wires embedded inside reference and sensing beads or pellistors. The sensing bead is coated with a catalyst so that combustible gases are oxidized if present. The heated beads operate in a bridge circuit that can produce a signal proportional to the concentration of combustible gas. Catalytic sensors require at least 10% by volume of Oxygen to operate properly and can be poisoned or inhibited by certain chemicals.
Infrared Sensors
Infrared sensors, or more specifically non-dispersive Infrared (NDIR) sensors, measure combustible gases and vapors in percent by volume (%Vol) ranges expressed as percent LEL (Lower Explosive Limit). NDIR sensors operate on the principle that hydrocarbon gases absorb specific wavelengths of infrared light. They are comprised of an infrared light source, reference and measurement detectors. The detector outputs are compared to indicate the presence of hazardous levels of gas. NDIR sensors do not require Oxygen to operate, always fail safe and cannot be poisoned.