Welcome to the NavList Message Boards.


A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

Compose Your Message

Add Images & Files
    Re: Radium illumination
    From: Gary LaPook
    Date: 2010 Sep 6, 11:04 -0700

    Since I used to assemble nuclear weapons I still have my dosimeters that measure the amount of radiation absorbed. I decided to see how much radiation was coming out of the A-7. I placed three different dosimeters with ranges of 0 to 200 milliroentgens, 0 to 1 roentgen and 0 to 200 roentgens, since I didn't know what level of radiation to expect, into the box with the A-7. Twelve hours later the most sensitive dosimeter registered 70 milliroentgens which was confirmed by the second dosimeter showing something less than a tenth of a roentgen and the least sensitive dosimeter registered no change.This means that the rate is about 6 milliroentgens per hour which would result in an exposure of about 50 roentgens per year, about 250 times the normal background exposure! Any exposure below 25 rems (approximately the same as a roentgen) produces no detectable clinical effects on humans so one could spend six months inside the sextant box without harm.

    But, of course, the dose rate is governed by the inverse square law meaning that the rate drops off based on the square of the distance. My dosimeters are about one inch from the bubble chamber but my TV watching couch is 15 feet (180 inches) away from the bookcase where I keep the sextant. 180 ^2 = 32,400 so the rate of radiation I receive from the sextant while sitting on my couch is only 0.185 microroentgens per hour, 1.6 milliroentgens per year above the normal background dose of about 200 milliroentgens per year. I guess that I won't loose a lot of sleep worrying about this.

    NavList message boards and member settings: www.fer3.com/NavList
    Members may optionally receive posts by email.
    To cancel email delivery, send a message to NoMail[at]fer3.com

    Browse Files

    Drop Files


    What is NavList?

    Join NavList

    (please, no nicknames or handles)
    Do you want to receive all group messages by email?
    Yes No

    You can also join by posting. Your first on-topic post automatically makes you a member.

    Posting Code

    Enter the email address associated with your NavList messages. Your posting code will be emailed to you immediately.

    Email Settings

    Posting Code:

    Custom Index

    Start date: (yyyymm dd)
    End date: (yyyymm dd)

    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site