Today’s PDF is entitled Personal Dosimeters for Radiological Defense it is actually from an old civil defense Technical Bulletin TB 11-2 of April 1952.
A dosimeter is a device worn by a per son for measuring and registering his total accumulated ionizing radiation exposure. Personal dosimeters are designed to measure exposures which may result during and after an atomic explosion in the 50 to 600 roentgen range. They should not be considered to be personal protection devices as they do nothing to reduce your exposure, only measure it.
Federal regulations limit a yearly dose to be the total effective dose equivalent equal to 5 rems, That is not a lot. Emergency exposures can be higher if you are a trained responder and you have had both a briefing on the biological effects of radiation and you volunteer (not be volun-told).
I used to teach radiological safety and dosimeter use, I have an article on the subject on this site. Additionally, if you want to know more, I have some other articles – including one on the basics of using a radiation meter.
When it comes to radiological protection, a lot of unscrupulous people sell Potassium iodide as a “radiation pill” it only protects on part of your body against one radiological material. I also have a post on that medicine.Personal Dosimeters for Radiological Defense (1952)