1C001 Category 1C

Materials “specially designed” for absorbing electromagnetic radiation, or intrinsically conductive polymers, as follows (see List of Items Controlled).

Category 1: Special Materials and Related Equipment, Chemicals, “Microorganisms,” and “Toxins”

Reasons for control

• NS: National security
• MT: Missile technology
• AT: Anti-terrorism

Country chart

List-based license exceptions

Items

1. a. Materials for absorbing frequencies exceeding 2 × 10 8 Hz but less than 3 × 10 12 Hz.
2. c. Intrinsically conductive polymeric materials with a 'bulk electrical conductivity' exceeding 10,000 S/m (Siemens per meter) or a 'sheet (surface) resistivity' of less than 100 ohms/square, based on any of the following polymers:
3. c.1. Polyaniline;
4. c.2. Polypyrrole;
5. c.3. Polythiophene;
6. c.4. Poly phenylene-vinylene; or
7. c.5. Poly thienylene-vinylene.

Related controls

See also 1C101.

Notes

Note 1: 1C001.a does not control: a. Hair type absorbers, constructed of natural or synthetic fibers, with non-magnetic loading to provide absorption; b. Absorbers having no magnetic loss and whose incident surface is non-planar in shape, including pyramids, cones, wedges and convoluted surfaces; c. Planar absorbers, having all of the following: 1. Made from any of the following: a. Plastic foam materials (flexible or non-flexible) with carbon-loading, or organic materials, including binders, providing more than 5% echo compared with metal over a bandwidth exceeding ±15% of the center frequency of the incident energy, and not capable of withstanding temperatures exceeding 450 K (177 °C); or b. Ceramic materials providing more than 20% echo compared with metal over a bandwidth exceeding ±15% of the center frequency of the incident energy, and not capable of withstanding temperatures exceeding 800 K (527 °C);

Technical Note: For the purposes of 1C001.a Note 1.c.1, absorption test samples should be a square at least 5 wavelengths of the center frequency on a side and positioned in the far field of the radiating element. 2. Tensile strength less than 7 × 10 6 N/m 2; and 3. Compressive strength less than 14 × 10 6 N/m 2; d. Planar absorbers made of sintered ferrite, having all of the following: 1. A specific gravity exceeding 4.4; and 2. A maximum operating temperature of 548 K (275 °C) or less; e. Planar absorbers having no magnetic loss and fabricated from 'open-cell foams' plastic material with a density of 0.15 grams/cm 3 or less.

Technical Note: For the purposes of 1C001.a Note e., 'open-cell foams' are flexible and porous materials, having an inner structure open to the atmosphere. 'Open-cell foams' are also known as reticulated foams.

Note 2: Nothing in Note 1 releases magnetic materials to provide absorption when contained in paint. b. Materials not transparent to visible light and “specially designed” for absorbing near-infrared radiation having a wavelength exceeding 810 nm but less than 2,000 nm (frequencies exceeding 150 THz but less than 370 THz);

Note: 1C001.b does not apply to materials, “specially designed” or formulated for any of the following applications: a. “Laser” marking of polymers; or b. “Laser” welding of polymers.

Note: 1C001.c does not apply to materials in a liquid form.

Technical Note: For the purposes of 1C001.c, 'bulk electrical conductivity' and 'sheet (surface) resistivity' should be determined using ASTM D-257 or national equivalents.

Source: eCFR, version 2026-08-01, retrieved 2026-08-20T04:04:59+00:00.