{
  "spore": "profile",
  "id": "conductive-elastomer-silver-aluminium",
  "spore_version": "0.2",
  "family": "conductive-elastomers",
  "name": "Silver-aluminium filled conductive elastomer (EMI gasket)",
  "abbreviation": "Ag/Al elastomer",
  "role": "EMI shielding gasket for enclosure seams",
  "category": "shielding",
  "type": "spot-shields",
  "summary": "Silver-aluminium filled conductive elastomers are EMI shielding gaskets for enclosure seams. Parker Chomerics CHO-SEAL 1285, with a silicone binder, is a MIL-DTL-83528 Type B material printed with at least 100 dB of plane-wave shielding at 10 GHz and a volume resistivity of 0.0080 ohm-cm. CHO-SEAL 1287, with a fluorosilicone binder, is a Type D material printed with at least 90 dB at 10 GHz and 0.012 ohm-cm. Both figures come from a reseller listing that attributes its data to Chomerics; no Parker datasheet could be opened in this run.\n",
  "best_for": "Enclosure seams in military and aerospace electronics that need a conductive gasket to MIL-DTL-83528 (CHO-SEAL 1285, Type B, at least 100 dB at 10 GHz, plane wave)",
  "weakest_at": "Long-term corrosion and shielding loss: the sources give only general galvanic guidance, and no outgassing, flight or chemical-resistance result for CHO-SEAL 1285 or 1287 was read in this run",
  "identity": {
    "formula": "Silicone (CHO-SEAL 1285) or fluorosilicone (CHO-SEAL 1287) elastomer binder filled with silver-plated aluminium particles, printed as Ag/Al",
    "designations": [
      {
        "system": "Trade name",
        "code": "CHO-SEAL 1285",
        "source": "lp-chomerics-1285",
        "where": "Page title and Trade Name field"
      },
      {
        "system": "Trade name",
        "code": "CHO-SEAL 1287",
        "source": "lp-chomerics-1287",
        "where": "Page title and Trade Name field"
      }
    ],
    "source": "lp-chomerics-1285",
    "where": "CHO-SEAL 1285 page, Descriptive Properties (Binder: Silicone; Filler: Ag/Al); CHO-SEAL 1287 page, Descriptive Properties (Base polymer: Fluoro-silicone; Filler: Ag/Al) and Material Notes (silver-plated-aluminum-filled fluorosilicone elastomer)"
  },
  "tags": {
    "environments": [],
    "stresses": [
      "thermal-cycling",
      "vibration"
    ],
    "applications": [
      "electronics-and-chips"
    ]
  },
  "properties": [
    {
      "benchmark": "density",
      "label": "Specific gravity, CHO-SEAL 1285 (silicone binder)",
      "value": 1.75,
      "value_high": 2.25,
      "bound": "range",
      "unit": "g/cc",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1285",
        "temperature": "not printed on the page"
      },
      "method": "Range printed as specific gravity with test standard ASTM D792 (the page labels it specific gravity, not density)",
      "status": "ground",
      "source": "lp-chomerics-1285",
      "where": "Physical Properties table, Specific Gravity row",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1285 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1285; Military-Aerospace Grade B; MIL-DTL-83528 Type B",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1285-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "hardness_shore_a",
      "label": "Hardness, Shore A, CHO-SEAL 1285",
      "value": 58,
      "value_high": 72,
      "bound": "range",
      "unit": "Shore A",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1285",
        "scale": "Shore A"
      },
      "method": "Range printed with test method ASTM D2240",
      "status": "ground",
      "source": "lp-chomerics-1285",
      "where": "Mechanical Properties table, Hardness, Shore A row",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1285 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1285; Military-Aerospace Grade B; MIL-DTL-83528 Type B",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1285-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Tensile strength at break, CHO-SEAL 1285",
      "value": 1.38,
      "bound": "lower",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1285",
        "printed_as": "1.38 MPa or more (200 psi or more)",
        "test": "ASTM D412"
      },
      "method": "Minimum printed with test method ASTM D412",
      "status": "ground",
      "source": "lp-chomerics-1285",
      "where": "Mechanical Properties table, Tensile Strength at Break row",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1285 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1285; Military-Aerospace Grade B; MIL-DTL-83528 Type B",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1285-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "elongation",
      "label": "Elongation at break, CHO-SEAL 1285",
      "value": 100,
      "value_high": 300,
      "bound": "range",
      "unit": "%",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1285",
        "test": "ASTM D412"
      },
      "method": "Range printed with test method ASTM D412",
      "status": "ground",
      "source": "lp-chomerics-1285",
      "where": "Mechanical Properties table, Elongation at Break row",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1285 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1285; Military-Aerospace Grade B; MIL-DTL-83528 Type B",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1285-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "tear_strength",
      "label": "Tear strength, CHO-SEAL 1285",
      "value": 5.25,
      "bound": "exact",
      "unit": "kN/m",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1285",
        "printed_alongside": "30.0 pli"
      },
      "method": "Typical value printed with test method ASTM D624",
      "status": "ground",
      "source": "lp-chomerics-1285",
      "where": "Mechanical Properties table, Tear Strength row",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1285 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1285; Military-Aerospace Grade B; MIL-DTL-83528 Type B",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1285-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "compression_set",
      "label": "Compression set, CHO-SEAL 1285",
      "value": 32,
      "bound": "upper",
      "unit": "%",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1285",
        "temperature": "100 °C",
        "time": "252000 sec (70.0 hours as printed)",
        "test": "ASTM D395 Method B"
      },
      "method": "Maximum printed with test method ASTM D395 Method B",
      "status": "ground",
      "source": "lp-chomerics-1285",
      "where": "Mechanical Properties table, Compression Set row",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1285 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1285; Military-Aerospace Grade B; MIL-DTL-83528 Type B",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1285-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "thermal_conductivity",
      "label": "Thermal conductivity, CHO-SEAL 1285",
      "value": 2.2,
      "bound": "exact",
      "unit": "W/m-K",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1285",
        "pressure": "2.07 MPa (300 psi as printed)",
        "test": "ASTM D5470"
      },
      "method": "Value printed with test method ASTM D5470 at the stated pressure",
      "status": "ground",
      "source": "lp-chomerics-1285",
      "where": "Thermal Properties table, Thermal Conductivity row",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1285 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1285; Military-Aerospace Grade B; MIL-DTL-83528 Type B",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1285-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "max_service_temp",
      "label": "Maximum service temperature in air, CHO-SEAL 1285",
      "value": 200,
      "bound": "exact",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1285",
        "environment": "air"
      },
      "method": "Value printed; the page lists the test method as Not listed",
      "status": "ground",
      "source": "lp-chomerics-1285",
      "where": "Thermal Properties table, Maximum Service Temperature, Air row",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1285 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1285; Military-Aerospace Grade B; MIL-DTL-83528 Type B",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1285-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "min_service_temp",
      "label": "Minimum service temperature in air, CHO-SEAL 1285",
      "value": -65,
      "bound": "exact",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1285",
        "environment": "air",
        "test": "Flex TR10; ASTM D1329"
      },
      "method": "Value printed with test method Flex TR10; ASTM D1329",
      "status": "ground",
      "source": "lp-chomerics-1285",
      "where": "Thermal Properties table, Minimum Service Temperature, Air row",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1285 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1285; Military-Aerospace Grade B; MIL-DTL-83528 Type B",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1285-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "electrical_resistivity",
      "label": "Volume resistivity, CHO-SEAL 1285",
      "value": 0.008,
      "bound": "exact",
      "unit": "ohm-cm",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1285",
        "state": "without pressure-sensitive adhesive",
        "test": "MIL-DTL-83528"
      },
      "method": "Value printed with the test named in the conditions",
      "status": "ground",
      "source": "lp-chomerics-1285",
      "where": "Electrical Properties table, Volume Resistivity row (first)",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1285 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1285; Military-Aerospace Grade B; MIL-DTL-83528 Type B",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1285-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "electrical_resistivity",
      "label": "Volume resistivity after tensile set, CHO-SEAL 1285",
      "value": 0.015,
      "bound": "exact",
      "unit": "ohm-cm",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1285",
        "state": "post tensile set",
        "test": "MIL-DTL-83528"
      },
      "method": "Value printed for the post-tensile-set condition",
      "status": "ground",
      "source": "lp-chomerics-1285",
      "where": "Electrical Properties table, Volume Resistivity row (second)",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1285 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1285; Military-Aerospace Grade B; MIL-DTL-83528 Type B",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1285-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "shielding_effectiveness",
      "label": "Shielding effectiveness, CHO-SEAL 1285, 200 kHz H field",
      "value": 60,
      "bound": "lower",
      "unit": "dB",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1285",
        "frequency": "200 kHz",
        "field": "H field",
        "standard": "MIL-DTL-83528 Para. 4.6.12"
      },
      "method": "Minimum printed as '>= 60 dB' in the listing",
      "status": "ground",
      "source": "lp-chomerics-1285",
      "where": "Shielding Effectiveness table, first row",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1285 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1285; Military-Aerospace Grade B; MIL-DTL-83528 Type B",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1285-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "shielding_effectiveness",
      "label": "Shielding effectiveness, CHO-SEAL 1285, 500 MHz E field",
      "value": 110,
      "bound": "lower",
      "unit": "dB",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1285",
        "frequency": "5.00e+8 Hz (500 MHz)",
        "field": "E field",
        "standard": "MIL-DTL-83528 Para. 4.6.12"
      },
      "method": "Minimum printed as '>= 110 dB' in the listing",
      "status": "ground",
      "source": "lp-chomerics-1285",
      "where": "Shielding Effectiveness table, row at 5.00e+8 Hz",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1285 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1285; Military-Aerospace Grade B; MIL-DTL-83528 Type B",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1285-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "shielding_effectiveness",
      "label": "Shielding effectiveness, CHO-SEAL 1285, 100 MHz E field",
      "value": 115,
      "bound": "lower",
      "unit": "dB",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1285",
        "frequency": "1.00e+8 Hz (100 MHz)",
        "field": "E field",
        "standard": "MIL-DTL-83528 Para. 4.6.12"
      },
      "method": "Minimum printed as '>= 115 dB' in the listing",
      "status": "ground",
      "source": "lp-chomerics-1285",
      "where": "Shielding Effectiveness table, row at 1.00e+8 Hz",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1285 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1285; Military-Aerospace Grade B; MIL-DTL-83528 Type B",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1285-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "shielding_effectiveness",
      "label": "Shielding effectiveness, CHO-SEAL 1285, 2 GHz plane wave",
      "value": 105,
      "bound": "lower",
      "unit": "dB",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1285",
        "frequency": "2.00e+9 Hz (2 GHz)",
        "field": "plane wave",
        "standard": "MIL-DTL-83528 Para. 4.6.12"
      },
      "method": "Minimum printed as '>= 105 dB' in the listing",
      "status": "ground",
      "source": "lp-chomerics-1285",
      "where": "Shielding Effectiveness table, row at 2.00e+9 Hz",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1285 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1285; Military-Aerospace Grade B; MIL-DTL-83528 Type B",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1285-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "shielding_effectiveness",
      "label": "Shielding effectiveness, CHO-SEAL 1285, 10 GHz plane wave",
      "value": 100,
      "bound": "lower",
      "unit": "dB",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1285",
        "frequency": "1.00e+10 Hz (10 GHz)",
        "field": "plane wave",
        "standard": "MIL-DTL-83528 Para. 4.6.12"
      },
      "method": "Minimum printed as '>= 100 dB' in the listing",
      "status": "ground",
      "source": "lp-chomerics-1285",
      "where": "Shielding Effectiveness table, row at 1.00e+10 Hz",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1285 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1285; Military-Aerospace Grade B; MIL-DTL-83528 Type B",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1285-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "heat_aged_volume_resistivity",
      "label": "Volume resistivity after heat ageing, CHO-SEAL 1285",
      "value": 0.01,
      "bound": "upper",
      "unit": "ohm-cm",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1285",
        "test": "MIL-DTL-83528 Para. 4.6.15",
        "exposure": "not printed on the page"
      },
      "method": "Maximum printed as '<0.01 ohm-cm' in the Descriptive Properties table",
      "status": "ground",
      "source": "lp-chomerics-1285",
      "where": "Descriptive Properties table, Heat Aging row",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1285 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1285; Military-Aerospace Grade B; MIL-DTL-83528 Type B",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1285-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "vibration_volume_resistivity",
      "label": "Volume resistivity after vibration, CHO-SEAL 1285",
      "value": 0.008,
      "bound": "upper",
      "unit": "ohm-cm",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1285",
        "test": "MIL-DTL-83528 Para. 4.6.13",
        "timing": "after vibration"
      },
      "method": "Maximum printed as '<0.008 ohm-cm'",
      "status": "ground",
      "source": "lp-chomerics-1285",
      "where": "Descriptive Properties table, Vibration Resistance, After row",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1285 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1285; Military-Aerospace Grade B; MIL-DTL-83528 Type B",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1285-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "vibration_volume_resistivity",
      "label": "Volume resistivity during vibration, CHO-SEAL 1285",
      "value": 0.012,
      "bound": "upper",
      "unit": "ohm-cm",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1285",
        "test": "MIL-DTL-83528 Para. 4.6.13",
        "timing": "during vibration"
      },
      "method": "Maximum printed as '<0.012 ohm-cm'",
      "status": "ground",
      "source": "lp-chomerics-1285",
      "where": "Descriptive Properties table, Vibration Resistance, During row",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1285 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1285; Military-Aerospace Grade B; MIL-DTL-83528 Type B",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1285-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "emp_survivability",
      "label": "EMP survivability, CHO-SEAL 1285",
      "value": 0.9,
      "bound": "lower",
      "unit": "kA/in",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1285",
        "test_method": "not printed on the page"
      },
      "method": "Minimum printed as '>0.9 kA / in'",
      "status": "ground",
      "source": "lp-chomerics-1285",
      "where": "Descriptive Properties table, EMP Survivability row",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1285 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1285; Military-Aerospace Grade B; MIL-DTL-83528 Type B",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1285-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "density",
      "label": "Specific gravity, CHO-SEAL 1287 (fluorosilicone binder)",
      "value": 1.75,
      "value_high": 2.25,
      "bound": "range",
      "unit": "g/cc",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1287",
        "temperature": "not printed on the page"
      },
      "method": "Range printed as specific gravity with test standard ASTM D792",
      "status": "ground",
      "source": "lp-chomerics-1287",
      "where": "Physical Properties table, Specific Gravity row",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1287 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1287; Military-Aerospace Type D; MIL-DTL-83528 Type D",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1287-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "hardness_shore_a",
      "label": "Hardness, Shore A, CHO-SEAL 1287",
      "value": 63,
      "value_high": 77,
      "bound": "range",
      "unit": "Shore A",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1287",
        "scale": "Shore A"
      },
      "method": "Range printed with test method ASTM D2240",
      "status": "ground",
      "source": "lp-chomerics-1287",
      "where": "Mechanical Properties table, Hardness, Shore A row",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1287 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1287; Military-Aerospace Type D; MIL-DTL-83528 Type D",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1287-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "ultimate_tensile_strength",
      "label": "Tensile strength at break, CHO-SEAL 1287",
      "value": 1.24,
      "bound": "lower",
      "unit": "MPa",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1287",
        "printed_as": "1.24 MPa or more (180 psi or more)",
        "test": "ASTM D412"
      },
      "method": "Minimum printed with test method ASTM D412",
      "status": "ground",
      "source": "lp-chomerics-1287",
      "where": "Mechanical Properties table, Tensile Strength at Break row",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1287 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1287; Military-Aerospace Type D; MIL-DTL-83528 Type D",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1287-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "elongation",
      "label": "Elongation at break, CHO-SEAL 1287",
      "value": 60,
      "value_high": 260,
      "bound": "range",
      "unit": "%",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1287",
        "test": "ASTM D412"
      },
      "method": "Range printed with test method ASTM D412",
      "status": "ground",
      "source": "lp-chomerics-1287",
      "where": "Mechanical Properties table, Elongation at Break row",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1287 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1287; Military-Aerospace Type D; MIL-DTL-83528 Type D",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1287-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "tear_strength",
      "label": "Tear strength, CHO-SEAL 1287",
      "value": 6.13,
      "bound": "exact",
      "unit": "kN/m",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1287",
        "printed_alongside": "35.0 pli"
      },
      "method": "Typical value printed with test method ASTM D624",
      "status": "ground",
      "source": "lp-chomerics-1287",
      "where": "Mechanical Properties table, Tear Strength row",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1287 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1287; Military-Aerospace Type D; MIL-DTL-83528 Type D",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1287-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "compression_set",
      "label": "Compression set, CHO-SEAL 1287",
      "value": 30,
      "bound": "upper",
      "unit": "%",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1287",
        "temperature": "100 °C",
        "time": "252000 sec (70.0 hours as printed at 212 °F)",
        "test": "ASTM D395 Method B"
      },
      "method": "Maximum printed with test method ASTM D395 Method B",
      "status": "ground",
      "source": "lp-chomerics-1287",
      "where": "Mechanical Properties table, Compression Set rows",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1287 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1287; Military-Aerospace Type D; MIL-DTL-83528 Type D",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1287-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "max_service_temp",
      "label": "Maximum service temperature in air, CHO-SEAL 1287",
      "value": 200,
      "bound": "exact",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1287",
        "environment": "air"
      },
      "method": "Value printed; no test method given on the page",
      "status": "ground",
      "source": "lp-chomerics-1287",
      "where": "Thermal Properties table, Maximum Service Temperature, Air row",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1287 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1287; Military-Aerospace Type D; MIL-DTL-83528 Type D",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1287-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "min_service_temp",
      "label": "Minimum service temperature in air, CHO-SEAL 1287",
      "value": -55,
      "bound": "exact",
      "unit": "°C",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1287",
        "environment": "air",
        "test": "Flex TR10; ASTM D1329"
      },
      "method": "Value printed with test method Flex TR10; ASTM D1329",
      "status": "ground",
      "source": "lp-chomerics-1287",
      "where": "Thermal Properties table, Minimum Service Temperature, Air row",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1287 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1287; Military-Aerospace Type D; MIL-DTL-83528 Type D",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1287-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "electrical_resistivity",
      "label": "Volume resistivity, CHO-SEAL 1287",
      "value": 0.012,
      "bound": "exact",
      "unit": "ohm-cm",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1287",
        "state": "without pressure-sensitive adhesive",
        "test": "MIL-DTL-83528"
      },
      "method": "Value printed with the test named in the conditions",
      "status": "ground",
      "source": "lp-chomerics-1287",
      "where": "Electrical Properties table, Volume Resistivity row (first)",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1287 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1287; Military-Aerospace Type D; MIL-DTL-83528 Type D",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1287-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "electrical_resistivity",
      "label": "Volume resistivity after tensile set, CHO-SEAL 1287",
      "value": 0.015,
      "bound": "exact",
      "unit": "ohm-cm",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1287",
        "state": "post tensile set",
        "test": "MIL-DTL-83528 Para. 4.6.9 as printed"
      },
      "method": "Value printed for the post-tensile-set condition; the page prints the standard as MIL-G-83528",
      "status": "ground",
      "note": "The page prints the standard reference as MIL-G-83528 in this row and MIL-DTL-83528 elsewhere.",
      "source": "lp-chomerics-1287",
      "where": "Electrical Properties table, Volume Resistivity row (second)",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1287 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1287; Military-Aerospace Type D; MIL-DTL-83528 Type D",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1287-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "shielding_effectiveness",
      "label": "Shielding effectiveness, CHO-SEAL 1287, 200 kHz H field",
      "value": 55,
      "bound": "lower",
      "unit": "dB",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1287",
        "frequency": "200 kHz",
        "field": "H field",
        "standard": "MIL-DTL-83528 Para. 4.6.12"
      },
      "method": "Minimum printed as '>= 55 dB' in the listing",
      "status": "ground",
      "source": "lp-chomerics-1287",
      "where": "Shielding Effectiveness table, first row",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1287 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1287; Military-Aerospace Type D; MIL-DTL-83528 Type D",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1287-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "shielding_effectiveness",
      "label": "Shielding effectiveness, CHO-SEAL 1287, 500 MHz E field",
      "value": 100,
      "bound": "lower",
      "unit": "dB",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1287",
        "frequency": "5.00e+8 Hz (500 MHz)",
        "field": "E field",
        "standard": "MIL-DTL-83528 Para. 4.6.12"
      },
      "method": "Minimum printed as '>= 100 dB' in the listing",
      "status": "ground",
      "source": "lp-chomerics-1287",
      "where": "Shielding Effectiveness table, row at 5.00e+8 Hz",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1287 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1287; Military-Aerospace Type D; MIL-DTL-83528 Type D",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1287-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "shielding_effectiveness",
      "label": "Shielding effectiveness, CHO-SEAL 1287, 100 MHz E field",
      "value": 110,
      "bound": "lower",
      "unit": "dB",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1287",
        "frequency": "1.00e+8 Hz (100 MHz)",
        "field": "E field",
        "standard": "MIL-DTL-83528 Para. 4.6.12"
      },
      "method": "Minimum printed as '>= 110 dB' in the listing",
      "status": "ground",
      "source": "lp-chomerics-1287",
      "where": "Shielding Effectiveness table, row at 1.00e+8 Hz",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1287 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1287; Military-Aerospace Type D; MIL-DTL-83528 Type D",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1287-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "shielding_effectiveness",
      "label": "Shielding effectiveness, CHO-SEAL 1287, 2 GHz plane wave",
      "value": 95,
      "bound": "lower",
      "unit": "dB",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1287",
        "frequency": "2.00e+9 Hz (2 GHz)",
        "field": "plane wave",
        "standard": "MIL-DTL-83528 Para. 4.6.12"
      },
      "method": "Minimum printed as '>= 95 dB' in the listing",
      "status": "ground",
      "source": "lp-chomerics-1287",
      "where": "Shielding Effectiveness table, row at 2.00e+9 Hz",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1287 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1287; Military-Aerospace Type D; MIL-DTL-83528 Type D",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1287-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "shielding_effectiveness",
      "label": "Shielding effectiveness, CHO-SEAL 1287, 10 GHz plane wave",
      "value": 90,
      "bound": "lower",
      "unit": "dB",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1287",
        "frequency": "1.00e+10 Hz (10 GHz)",
        "field": "plane wave",
        "standard": "MIL-DTL-83528 Para. 4.6.12"
      },
      "method": "Minimum printed as '>= 90 dB' in the listing",
      "status": "ground",
      "source": "lp-chomerics-1287",
      "where": "Shielding Effectiveness table, row at 1.00e+10 Hz",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1287 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1287; Military-Aerospace Type D; MIL-DTL-83528 Type D",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1287-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "shielding_effectiveness",
      "label": "Shielding effectiveness, CHO-SEAL 1287, 40 GHz plane wave",
      "value": 75,
      "bound": "lower",
      "unit": "dB",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1287",
        "frequency": "4.00e+10 Hz (40 GHz)",
        "field": "plane wave",
        "standard": "MIL-DTL-83528 Para. 4.6.12"
      },
      "method": "Minimum printed as '>= 75 dB' in the listing",
      "status": "ground",
      "source": "lp-chomerics-1287",
      "where": "Shielding Effectiveness table, row at 4.00e+10 Hz",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1287 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1287; Military-Aerospace Type D; MIL-DTL-83528 Type D",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1287-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "heat_aged_volume_resistivity",
      "label": "Volume resistivity after heat ageing, CHO-SEAL 1287",
      "value": 0.015,
      "bound": "upper",
      "unit": "ohm-cm",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1287",
        "test": "MIL-DTL-83528 Para. 4.6.15",
        "exposure": "not printed on the page"
      },
      "method": "Maximum printed as '<0.015 ohm-cm'",
      "status": "ground",
      "source": "lp-chomerics-1287",
      "where": "Descriptive Properties table, Heat Aging row",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1287 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1287; Military-Aerospace Type D; MIL-DTL-83528 Type D",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1287-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "vibration_volume_resistivity",
      "label": "Volume resistivity after vibration, CHO-SEAL 1287",
      "value": 0.012,
      "bound": "upper",
      "unit": "ohm-cm",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1287",
        "test": "MIL-DTL-83528 Para. 4.6.13",
        "timing": "after vibration"
      },
      "method": "Maximum printed as '<0.012 ohm-cm'",
      "status": "ground",
      "source": "lp-chomerics-1287",
      "where": "Descriptive Properties table, Vibration Resistance, After row",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1287 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1287; Military-Aerospace Type D; MIL-DTL-83528 Type D",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1287-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "vibration_volume_resistivity",
      "label": "Volume resistivity during vibration, CHO-SEAL 1287",
      "value": 0.015,
      "bound": "upper",
      "unit": "ohm-cm",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1287",
        "test": "MIL-DTL-83528 Para. 4.6.13",
        "timing": "during vibration"
      },
      "method": "Maximum printed as '<0.015 ohm-cm'",
      "status": "ground",
      "source": "lp-chomerics-1287",
      "where": "Descriptive Properties table, Vibration Resistance, During row",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1287 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1287; Military-Aerospace Type D; MIL-DTL-83528 Type D",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1287-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    },
    {
      "benchmark": "emp_survivability",
      "label": "EMP survivability, CHO-SEAL 1287",
      "value": 0.9,
      "bound": "lower",
      "unit": "kA/in",
      "scope": "material",
      "conditions": {
        "product": "CHO-SEAL 1287",
        "test": "MIL-DTL-83528 Para. 4.6.16"
      },
      "method": "Minimum printed as '>0.9 kA / in' with the test paragraph named on the page",
      "status": "ground",
      "source": "lp-chomerics-1287",
      "where": "Descriptive Properties table, EMP Survivability row",
      "source_detail": {
        "title": "Parker Chomerics CHO-SEAL 1287 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
        "id": "CHO-SEAL 1287; Military-Aerospace Type D; MIL-DTL-83528 Type D",
        "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1287-Conductive-Elastomer.php",
        "year": 2026,
        "kind": "web",
        "license": "reseller listing, linked not reproduced"
      }
    }
  ],
  "corrosion": [
    {
      "environment": "Silver/aluminium filler in contact with aluminium housings (galvanic exposure)",
      "headline": "Silver/aluminium fillers pair well with aluminium housings and reduce galvanic risk, according to a Modus Advanced guide on space-qualified EMI gaskets.",
      "effect": "The guide's filler table rates silver/aluminium as good with aluminium housings, and its galvanic section says the filler reduces galvanic risk. It also says plating the housing with nickel or tin improves galvanic compatibility. No corrosion test on CHO-SEAL 1285 or 1287 was read.",
      "rating": "low",
      "conditions": {
        "basis": "general vendor guidance, no test condition, exposure time or product named",
        "housing": "aluminium"
      },
      "source": "modus-emi-guide",
      "where": "Filler Comparison table; Galvanic Compatibility section; Designing for Manufacturability section"
    },
    {
      "environment": "Thermal cycling combined with galvanic exposure over a mission",
      "headline": "The Modus guide says thermal cycling and galvanic effects together can reduce shielding by several dB over a mission.",
      "effect": "The guide states that the combination of thermal cycling and galvanic effects can reduce shielding effectiveness by several dB over the life of a mission, and that wrong filler and housing pairings can increase contact resistance over time. The guide gives no dB figure or time for this loss.",
      "rating": "moderate",
      "conditions": {
        "basis": "vendor statement, no mission duration or dB figure given",
        "product": "silver/aluminium filled gaskets in general"
      },
      "source": "modus-emi-guide",
      "where": "Thermal Cycling section; Galvanic Compatibility section"
    },
    {
      "environment": "Heat ageing at the MIL-DTL-83528 test condition",
      "headline": "After heat ageing, the listed volume resistivity stays below 0.01 ohm-cm for CHO-SEAL 1285 and below 0.015 ohm-cm for CHO-SEAL 1287.",
      "effect": "The Descriptive Properties tables of both Chomerics listings print a heat-ageing resistivity limit under MIL-DTL-83528 Para. 4.6.15. The exposure temperature and time are not printed on the pages, so the limit cannot be tied to a service life.",
      "rating": "low",
      "conditions": {
        "basis": "maximum limits as printed; exposure temperature and time not printed",
        "standard": "MIL-DTL-83528 Para. 4.6.15"
      },
      "source": "lp-chomerics-1285",
      "where": "Descriptive Properties table, Heat Aging row (1285); the 1287 page gives the 1287 row"
    },
    {
      "environment": "Corrosion resistance claim on the CHO-SEAL 1285 listing",
      "headline": "The CHO-SEAL 1285 listing describes the material as having improved corrosion resistance but gives no test figure for it.",
      "effect": "The listing's Material Notes say 'Conductive Elastomer with Improved Corrosion Resistance'. The page does not name the comparison material, the test or the result, so the claim is recorded as printed and not rated.",
      "rating": "unknown",
      "conditions": {
        "basis": "manufacturer claim as printed on a reseller listing",
        "comparison": "not stated"
      },
      "source": "lp-chomerics-1285",
      "where": "Material Notes"
    }
  ],
  "risks": {
    "hazards": [
      {
        "text": "Silver, as the plating on the filler particles (bare metal, powder or nano form): PubChem's EU entries give 'Very toxic to aquatic life with long lasting effects' and 'Very toxic to aquatic life' with signal word 'Warning' and the environmental hazard pictogram. Japanese NITE entries list 'May cause an allergic skin reaction' and 'Causes eye irritation' with signal word 'Danger'. These are GHS data for the bare metal, not for the gasket.",
        "ghs": [
          "H410",
          "H400",
          "H317",
          "H320"
        ],
        "source": "pubchem-silver",
        "where": "Safety and Hazards, GHS Classification (CID 23954)"
      },
      {
        "text": "Aluminium, as the base metal of the filler particles (powder form): PubChem's ECHA aggregate and most EU entries give 'In contact with water releases flammable gas' with signal word 'Danger' and the flammable pictogram. Stabilised aluminium powder is listed as 'Flammable solid', and a pyrophoric powder entry as 'Catches fire spontaneously if exposed to air'. Japanese NITE-CMC entries add 'Causes damage to organs' and 'Causes damage to organs through prolonged or repeated exposure'. These are GHS data for the bare powder, not for the gasket.",
        "ghs": [
          "H261",
          "H228",
          "H250",
          "H370",
          "H372"
        ],
        "source": "pubchem-aluminium",
        "where": "Safety and Hazards, GHS Classification (CID 5359268)"
      }
    ],
    "failure_risks": [
      {
        "mode": "Galvanic corrosion at the gasket-to-housing interface",
        "trigger": "Silver/aluminium filler in contact with a housing that is not plated or otherwise matched, in a humid or thermally cycled environment",
        "consequence": "The Modus guide says wrong filler and housing pairings can lead to increased contact resistance over time, which reduces shielding.",
        "severity": "moderate",
        "source": "modus-emi-guide",
        "where": "Galvanic Compatibility section"
      },
      {
        "mode": "Shielding loss from thermal cycling over a mission",
        "trigger": "Repeated thermal cycling of a gasket seam over the life of a mission",
        "consequence": "The guide says the combined effects can reduce shielding effectiveness by several dB over the life of a mission. No dB value or time is given.",
        "severity": "moderate",
        "source": "modus-emi-guide",
        "where": "Thermal Cycling section"
      }
    ],
    "side_effects": [],
    "handling": [],
    "mitigations": [
      {
        "text": "Plate aluminium housings with nickel or tin to improve galvanic compatibility, as the Modus guide recommends for silver/aluminium gaskets.",
        "source": "modus-emi-guide",
        "where": "Designing for Manufacturability section"
      }
    ]
  },
  "uses": [
    {
      "application": "electronics-and-chips",
      "device": "EMI gasket on enclosure flanges and covers in military electronics (MIL-DTL-83528 scope)",
      "example": "The MIL-DTL-83528 specification covers conductive elastomeric shielding gaskets that give low interface resistance between enclosure flanges or covers and provide environmental sealing. CHO-SEAL 1285 is listed as a Military-Aerospace Type B material to that specification.",
      "source": "everyspec-mil-83528",
      "where": "Scope summary; CHO-SEAL 1285 page, Grade and Type fields"
    },
    {
      "application": "electronics-and-chips",
      "device": "EMI gasket for satellite electronics enclosures (vendor guidance, no flight result read)",
      "example": "A Modus Advanced guide on space-qualified EMI gaskets for satellite shielding discusses silver/aluminium fillers for this use. The guide gives no flight result for CHO-SEAL 1285 or 1287.",
      "source": "modus-emi-guide",
      "where": "Page title; FAQ heading 'Which conductive filler is best for satellite applications?'"
    }
  ],
  "supply": [
    {
      "subject": "Silver (filler metal)",
      "abundance": "Not read in this run. The USGS silver chapter was read for production, reserves and recycling only.",
      "producers": [
        {
          "country": "Mexico",
          "share_percent": 24.2,
          "year": 2025
        },
        {
          "country": "Peru",
          "share_percent": 13.8,
          "year": 2025
        },
        {
          "country": "China",
          "share_percent": 13.1,
          "year": 2025
        },
        {
          "country": "Bolivia",
          "share_percent": 5.8,
          "year": 2025
        },
        {
          "country": "Chile",
          "share_percent": 5.4,
          "year": 2025
        }
      ],
      "critical_lists": [
        {
          "list": "USGS 2025 List of Critical Minerals",
          "listed": true
        }
      ],
      "recycling": "USGS: about 1,000 tons of silver was recovered from new and old scrap in the United States in 2025, about 11% of apparent consumption.",
      "substitutes": [
        "USGS: aluminum and rhodium may replace silver in mirrors and reflecting surfaces. The chapter names no substitute for silver in conductive elastomers."
      ],
      "source": "usgs-mcs2026-silver",
      "where": "Domestic Production and Use; Recycling; World Mine Production and Reserves table (2025e: Mexico 6,300, Peru 3,600, China 3,400, Bolivia 1,500, Chile 1,400 of a 26,000 world total); Substitutes. Shares calculated by Space Mushroom against the printed world total."
    },
    {
      "subject": "Aluminium (filler base metal)",
      "abundance": "Not read in this run.",
      "producers": [
        {
          "country": "China",
          "share_percent": 60.8,
          "year": 2025
        },
        {
          "country": "India",
          "share_percent": 5.7,
          "year": 2025
        },
        {
          "country": "Russia",
          "share_percent": 5.3,
          "year": 2025
        },
        {
          "country": "Canada",
          "share_percent": 4.5,
          "year": 2025
        },
        {
          "country": "United Arab Emirates",
          "share_percent": 3.6,
          "year": 2025
        }
      ],
      "critical_lists": [
        {
          "list": "USGS 2025 List of Critical Minerals",
          "listed": true
        }
      ],
      "recycling": "USGS: about 3.6 million tons of aluminum was recovered from purchased scrap in the United States in 2025, equivalent to about 28% of apparent consumption from old scrap.",
      "substitutes": [
        "USGS: copper can replace aluminum in electrical and heat-exchange applications."
      ],
      "source": "usgs-mcs2026-aluminum",
      "where": "World Smelter Production and Capacity table (2025e: China 45,000 of a 74,000 world total, India 4,200, Russia 3,900, Canada 3,300, United Arab Emirates 2,700); Recycling; Substitutes. Shares calculated by Space Mushroom against the printed world total (rounded). Smelter output, not mine output."
    }
  ],
  "media": [],
  "documents": [
    {
      "title": "Parker Chomerics CHO-SEAL 1285 listing (lookpolymers.com, data attributed to Chomerics)",
      "type": "datasheet",
      "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1285-Conductive-Elastomer.php"
    },
    {
      "title": "Parker Chomerics CHO-SEAL 1287 listing (lookpolymers.com, data attributed to Chomerics)",
      "type": "datasheet",
      "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1287-Conductive-Elastomer.php"
    },
    {
      "title": "MIL-DTL-83528E, Gaskets, Electrically Conductive Elastomeric, Shielding (EverySpec summary page)",
      "type": "standard",
      "url": "https://everyspec.com/MIL-SPECS/MIL-SPECS-MIL-DTL/MIL-DTL-83528E_52081/",
      "year": 2012
    },
    {
      "title": "USGS Mineral Commodity Summaries 2026: Silver",
      "type": "report",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-silver.pdf",
      "year": 2026
    },
    {
      "title": "USGS Mineral Commodity Summaries 2026: Aluminum",
      "type": "report",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-aluminum.pdf",
      "year": 2026
    },
    {
      "title": "PubChem compound record for Silver (CID 23954), GHS Classification",
      "type": "database",
      "url": "https://pubchem.ncbi.nlm.nih.gov/compound/23954"
    },
    {
      "title": "PubChem compound record for Aluminum (CID 5359268), GHS Classification",
      "type": "database",
      "url": "https://pubchem.ncbi.nlm.nih.gov/compound/5359268"
    }
  ],
  "gaps": [
    "No Parker Chomerics datasheet or product page could be opened in this run: the Parker selector guide, the NASA outgassing PDF, the CHO-TM-TP09 test procedure and the ph.parker.com product pages returned HTTP 403, and the Mouser listing timed out. All CHO-SEAL values come from two reseller pages that state the information is provided by Chomerics.",
    "Outgassing (ASTM E595 total mass loss and CVCM) for CHO-SEAL 1285 or 1287 was not read on a fetched page. A search summary mentioned Parker outgassing figures, but they were not opened and are not recorded here.",
    "No flight, space-environment or vacuum result for CHO-SEAL 1285 or 1287 was read. The space use in the uses section is vendor guidance, not a flight record.",
    "The MIL-DTL-83528 per-type plane-wave shielding table was not read. The EverySpec page shows only the scope and revision list, and the PDF returned HTTP 404.",
    "The revision of MIL-DTL-83528 that governs CHO-SEAL 1285 and 1287 is not confirmed. The EverySpec page shows Rev. E dated 2012 with later revisions F and G listed; the revision letter cited by each Chomerics listing is not printed.",
    "No safety data sheet for CHO-SEAL 1285 or 1287 was read. The hazards entries use PubChem GHS data for the constituent silver and aluminium metals in powder form, not for the gasket, so the gasket's own hazard classification is not recorded. A search returned SDSs only for other silver-aluminium or nickel-graphite products, which were not used.",
    "Binder and filler mass shares, and the composition of the silver-plated aluminium particles, are not printed in any source read.",
    "Thermal conductivity is printed for CHO-SEAL 1285 only; the CHO-SEAL 1287 listing prints none.",
    "Chemical resistance, salt-fog or humidity corrosion data, and galvanic test data for CHO-SEAL 1285 or 1287 were not found in any source read. The corrosion-resistance claim on the 1285 listing has no figure.",
    "Hardness (Shore A), tear strength, compression set, heat-ageing and vibration resistivity, and EMP survivability are not in the properties canon; they use short snake_case names (hardness_shore_a, tear_strength, compression_set, heat_aged_volume_resistivity, vibration_volume_resistivity, emp_survivability).",
    "Shielding effectiveness values are the listing's minimum values for two grades, not measured data on a stated gasket size or seam. The conditions for the seam, compression and mounting are not printed.",
    "Abundance (crustal) of silver and aluminium and the EU critical raw materials list were not read in this run.",
    "No comparison with other shielding profiles in this collection was made; their values were not read for this profile."
  ],
  "story": {
    "why": "Conductive elastomer EMI gaskets seal an enclosure seam and carry its shielding current across the joint. CHO-SEAL 1285 and CHO-SEAL 1287 are Parker Chomerics silver-aluminium filled gaskets built to the MIL-DTL-83528 specification. The 1285 has a silicone binder and is listed as Type B, with at least 100 dB of plane-wave shielding at 10 GHz. The 1287 has a fluorosilicone binder and is listed as Type D, with at least 90 dB at 10 GHz. The choice between them depends on the binder and the shielding frequency needed.",
    "uses": [
      {
        "where": "Military and aerospace electronics",
        "line": "The MIL-DTL-83528 specification covers electrically conductive elastomeric shielding gaskets that give low interface resistance between enclosure flanges or covers and also provide environmental sealing. CHO-SEAL 1285 is listed as a Type B material to that specification."
      },
      {
        "where": "Satellite electronics (vendor guidance only)",
        "line": "A Modus Advanced guide on space-qualified EMI gaskets for satellite shielding discusses silver/aluminium fillers for this use. The guide does not give a flight result for these two grades."
      }
    ],
    "can_do": [
      {
        "label": "Shielding",
        "line": "Per the CHO-SEAL 1285 listing, the minimum plane-wave shielding effectiveness is 100 dB at 10 GHz (1.00e+10 Hz) and 110 dB at 500 MHz for the E field. The 1287 listing gives 90 dB at 10 GHz and 100 dB at 500 MHz for the E field.",
        "benchmark": "shielding_effectiveness",
        "scope": "material",
        "value": "At least 100 dB at 10 GHz"
      },
      {
        "label": "Conductivity",
        "line": "The 1285 listing prints a volume resistivity of 0.0080 ohm-cm without pressure-sensitive adhesive, and 0.015 ohm-cm after tensile set. The 1287 listing prints 0.012 ohm-cm and 0.015 ohm-cm.",
        "benchmark": "electrical_resistivity",
        "scope": "material",
        "value": "0.0080 ohm-cm"
      },
      {
        "label": "Temperature",
        "line": "Both listings print a maximum service temperature in air of 200 °C. The 1285 minimum is -65 °C and the 1287 minimum is -55 °C, both per the Flex TR10 and ASTM D1329 test named on the pages.",
        "benchmark": "max_service_temp",
        "scope": "material",
        "value": "200 °C in air"
      }
    ],
    "compare": "This profile compares two grades from one manufacturer rather than other shielding materials. CHO-SEAL 1285 (silicone, Type B) lists at least 100 dB at 10 GHz and 0.0080 ohm-cm volume resistivity. CHO-SEAL 1287 (fluorosilicone, Type D) lists at least 90 dB at 10 GHz and 0.012 ohm-cm. The two grades are not interchangeable: the binder changes the shielding minima and the resistivity as printed.",
    "compare_rows": [
      {
        "label": "Specific gravity",
        "benchmark": "density",
        "scope": "material"
      },
      {
        "label": "Volume resistivity",
        "benchmark": "electrical_resistivity",
        "scope": "material"
      },
      {
        "label": "Shielding effectiveness",
        "benchmark": "shielding_effectiveness",
        "scope": "material"
      }
    ],
    "handling": [
      "No handling source was read for CHO-SEAL 1285 or 1287. Check the supplier's safety data sheet for the exact part.",
      "The listed service range is -65 °C to 200 °C in air for CHO-SEAL 1285 and -55 °C to 200 °C for CHO-SEAL 1287.",
      "Specify the grade by name, since the binder and the minimum temperature differ between 1285 and 1287."
    ],
    "good_for": [
      "Enclosure seams that need a conductive gasket to MIL-DTL-83528. CHO-SEAL 1285 is listed as Type B with at least 100 dB at 10 GHz.",
      "Seams that must stay conductive through vibration: volume resistivity after vibration is printed as below 0.008 ohm-cm for CHO-SEAL 1285."
    ],
    "watch_out": [
      "Galvanic pairing: the Modus guide says the filler suits aluminium housings but the pairing still needs plating or matching to avoid contact-resistance rise over time.",
      "Thermal cycling: the guide says shielding can fall by several dB over a mission. No time or dB figure is given.",
      "Outgassing and flight data: none were read for these two grades, so their suitability for vacuum use is not established by these sources."
    ],
    "verdict": "CHO-SEAL 1285 and 1287 are MIL-DTL-83528 silver-aluminium gaskets with printed shielding minima and volume resistivity. The sources read give listing values only: no Parker datasheet, outgassing, hazard or flight data could be checked in this run.",
    "recipe": {
      "line": "CHO-SEAL gaskets are a conductive elastomer: a cured silicone or fluorosilicone binder filled with silver-plated aluminium particles, printed as Ag/Al. The binder gives the rubber sealing and resilience; the filler gives the electrical conductivity. Shares of binder and filler are not printed in any source read.",
      "parts": [
        {
          "name": "Silicone or fluorosilicone elastomer binder",
          "role": "The rubber matrix. It gives the gasket its hardness, elongation and sealing; CHO-SEAL 1285 uses a silicone binder and CHO-SEAL 1287 a fluorosilicone binder.",
          "share_note": "Mass share not printed in the sources read"
        },
        {
          "name": "Silver-plated aluminium particles (Ag/Al)",
          "role": "The conductive filler. Silver on aluminium particles provides the electrical path that gives the shielding and the low volume resistivity.",
          "share_note": "Mass share not printed in the sources read"
        }
      ]
    },
    "risk_groups": [
      {
        "title": "For people",
        "lead": "No safety data sheet for CHO-SEAL 1285 or 1287 was read in this run, so their own hazard classification is not recorded. PubChem GHS data for the constituent silver and aluminium metals is in the hazards section.",
        "points": [
          {
            "label": "Hazard data",
            "line": "The sources read give no hazard classification for these two gasket grades. Read the supplier's safety data sheet for the exact part before handling."
          }
        ],
        "level": 0,
        "verdict": "Not checked"
      },
      {
        "title": "If it fails",
        "lead": "The failure routes in the sources read are electrical: loss of shielding and contact resistance over time.",
        "points": [
          {
            "label": "Galvanic and thermal",
            "line": "The Modus guide says wrong filler and housing pairings can raise contact resistance over time, and that thermal cycling plus galvanic effects can reduce shielding by several dB over a mission. It gives no time or dB figure."
          }
        ]
      }
    ]
  },
  "updated": "2026-11-01",
  "review": {
    "status": "draft",
    "method": "assistant",
    "checked_values": 40,
    "unreachable": 5,
    "caveats": 5,
    "note": "Read by an AI assistant on 2026-11-01. All CHO-SEAL values come from two reseller listings that attribute the data to Chomerics; the Parker pages, the NASA outgassing PDF and the MIL-DTL-83528 PDF could not be opened. Unreachable: Parker selector guide, Parker product page, Parker CHO-TM-TP09 procedure, Parker NASA outgassing PDF (all HTTP 403), and the MIL-DTL-83528 PDF (HTTP 404). Caveats: values are typical or minimum listing figures; the shielding minima are for one test set-up; the 1287 resistivity row cites MIL-G-83528; the specific gravity is not a density."
  },
  "sources": {
    "lp-chomerics-1285": {
      "title": "Parker Chomerics CHO-SEAL 1285 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
      "id": "CHO-SEAL 1285; Military-Aerospace Grade B; MIL-DTL-83528 Type B",
      "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1285-Conductive-Elastomer.php",
      "year": 2026,
      "kind": "web",
      "license": "reseller listing, linked not reproduced"
    },
    "lp-chomerics-1287": {
      "title": "Parker Chomerics CHO-SEAL 1287 Conductive Elastomer (product listing on lookpolymers.com; information provided by Chomerics)",
      "id": "CHO-SEAL 1287; Military-Aerospace Type D; MIL-DTL-83528 Type D",
      "url": "https://www.lookpolymers.com/polymer_Parker-Chomerics-CHO-SEAL-1287-Conductive-Elastomer.php",
      "year": 2026,
      "kind": "web",
      "license": "reseller listing, linked not reproduced"
    },
    "everyspec-mil-83528": {
      "title": "MIL-DTL-83528E, Gaskets, Electrically Conductive Elastomeric, Shielding (summary page)",
      "id": "MIL-DTL-83528E, dated 13-AUG-2012 (Rev. E listed as 08-2012)",
      "url": "https://everyspec.com/MIL-SPECS/MIL-SPECS-MIL-DTL/MIL-DTL-83528E_52081/",
      "year": 2012,
      "kind": "standard",
      "license": "standard summary, linked not reproduced"
    },
    "ssp-mil-83528-guide": {
      "title": "Military Gaskets for EMI Shielding: What are MIL-DTL-83528 and QPL 83528? (Specialty Silicone Products)",
      "id": "SSP web article on MIL-DTL-83528 sections A, B, C, D and K",
      "url": "https://sspinc.com/?p=11006",
      "kind": "web",
      "license": "vendor article, linked not reproduced"
    },
    "modus-emi-guide": {
      "title": "Space-Qualified EMI Gasket Selection: A Material Guide for Satellite Shielding (Modus Advanced)",
      "id": "Modus Advanced blog guide",
      "url": "https://www.modusadvanced.com/resources/blog/space-qualified-emi-gasket-selection-a-material-guide-for-satellite-shielding-1",
      "kind": "web",
      "license": "vendor article, linked not reproduced"
    },
    "usgs-mcs2026-silver": {
      "title": "Mineral Commodity Summaries 2026, Silver",
      "id": "USGS MCS 2026, February 2026",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-silver.pdf",
      "year": 2026,
      "kind": "report",
      "license": "public domain (USGS)"
    },
    "usgs-mcs2026-aluminum": {
      "title": "Mineral Commodity Summaries 2026, Aluminum",
      "id": "USGS MCS 2026, February 2026",
      "url": "https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-aluminum.pdf",
      "year": 2026,
      "kind": "report",
      "license": "public domain (USGS)"
    },
    "usgs-crit2025": {
      "title": "About the 2025 List of Critical Minerals (USGS, final list)",
      "id": "Final 2025 List of Critical Minerals, November 2025",
      "url": "https://www.usgs.gov/programs/mineral-resources-program/science/about-2025-list-critical-minerals",
      "year": 2025,
      "kind": "web",
      "license": "public domain (USGS)"
    },
    "pubchem-silver": {
      "title": "PubChem compound record for Silver (CID 23954), GHS Classification",
      "id": "PubChem CID 23954",
      "url": "https://pubchem.ncbi.nlm.nih.gov/compound/23954",
      "kind": "database",
      "license": "public domain (NCBI PubChem), linked not reproduced"
    },
    "pubchem-aluminium": {
      "title": "PubChem compound record for Aluminum (CID 5359268), GHS Classification",
      "id": "PubChem CID 5359268",
      "url": "https://pubchem.ncbi.nlm.nih.gov/compound/5359268",
      "kind": "database",
      "license": "public domain (NCBI PubChem), linked not reproduced"
    }
  },
  "license": "CC-BY-4.0",
  "url": "https://spacemushroom.com/profiles/conductive-elastomer-silver-aluminium/"
}