A better way to track hazardous chemical inventories

For chemists who track inventory of laboratory chemicals, radio-frequency identification (RFID) tags can reveal which chemicals are in a storage space much quicker than keeping track of inventory with traditional labels or using bar codes. And because RFID readers don’t require a line of sight to their target, the tags allow scientists to track dangerous chemicals from a distance without direct interaction.

You can simply point a reader in the direction of several RFID-tagged chemical containers and quickly know what’s present, says Raul Baez Lara Jr., a performance measurement specialist at Lawrence Livermore National Laboratory (LLNL).

But RFID tagging often isn’t compatible with metal chemical containers, which have limited RFID adoption because metal can interfere with a tag’s radio signal. This particularly affects labs like LLNL that work with hazardous radioactive materials, light-sensitive photographic chemicals, pressurized gases, and oily liquids, which are often kept in metal containers. In a new study, Lara’s team explores how best to place RFID tags onto these substances’ metal casings (ACS Chem. Health Saf. 2025, DOI: 10.1021/acs.chas.4c00104).

Lara’s team found that flag tags with RFID that stick out from a metal surface give signals that are more reliable and that can be read from farther away than those from tags stuck directly onto containers. Identifying items with RFID tags was 65% quicker than sight-reading labels and 52% faster than scanning bar codes. Also, bar codes fade with prolonged exposure to ultraviolet light, making them more difficult to read over time, a problem especially for containers stored outdoors.

The researchers went a step further by designing small 3D-printed mounts for the RFID tags that keep them slightly lifted from the metal surfaces. In the study, the authors found that one scenario using printed mounts resulted in a 235% increase in the reading distance.