Van Allen Belt Dosimeter (VABD)
The Van Allen Belt Dosimeter (VABD) was designed specifically for Apollo dosimetery within these radiation belts. The VABD had a greater than 180 degree radiation acceptance angle which had been shown to work well in the Van Allen Belts. The ionization-chamber walls of the VABD were constructed of aluminum instead of tissue-equivalent plastic because of a flammability concern. The VABD was stored in the command module.