Android version of my Density variation calculator.
It is a simple app that calculates allowable density variation under the rules of ASME Section V.
You measure the density in the body of a hole type IQI or next to the essential wire of a wire type IQI and then it calculates the min and max densities in the area of interest. The ranges are minus 15% to plus 30% ( except the plus 30% can be exceeded when using a shim under a hole type IQI).
An Industrial Radiography Barricade Calculator for double checking your barricade or Restricted Area.
The app calculates four numbers that can be handy when performing radiography. The distance with your collimator and shielding, the distance without them (in case the open end of the collimator is unavoidably pointing towards a barricade, the emergency distance (worse case scenario of no shielding and 2 mR/hr), and also the maximum allowable survey meter reading at the barricade when performing compliance verifications.
The dose rate reading is rounded off at 0.1 precision level so don’t push the readings to the limit. More room is better.
The distances are ALL rounded up to the next whole number if they are not a whole number. For example, 50.001 feet will display as 51 feet. And decimal point whatsoever will cause the answer to be rounded up to the next whole number.
I only have the input for time in Minutes. There is a reason for it. If you have such a short time of exposure that the total amount of all exposures is less than 1 minute, you can afford to round up. The distances will be really short. If you are shooting 5 minutes and 30 seconds I would recommend putting at least 6 minutes in you calculations, if not 7, or 8, or 10.
The same goes with curies. It wouldn’t hurt to over estimate your curies. Complying with the regulations by having a little more barricade than needed is better than having too little.
These calculations are your responsibility and this is just made for you to double check yourself. No responsibility for compliance is accepted.
I have had a lot of people email and ask about the math formulas to calculate Radiographic Enlargement.
If you look in many of the handbooks and online you will mostly find very complicated formulas. In reality it is quite simple and just uses basic ratios. The formula below is for using a steel comparator ball but the math works the same if regardless.
Actual Pipe Wall = (Actual Ball Diameter ÷ Ball Diameter on Film) X Wall Thickness on Film
Divide the actual ball diameter or the length of the optical comparator by the measured apparent length of the comparitor on the film. Multiply this answer by the pipe wall thickness as measured on the film.
For accurate measurement the ball or comparator block must be put as near as possible to the exact side of the pipe parallel to the film so that the enlargement of the pipe wall is the same as that of the ball of block.
If the comparator or ball is not touching the pipe because of insulation, aim the source at the center of the space between the two, as shown in the drawing below. This will help insure an equal amount of enlargement to the ball and the pipe wall. (Think of how the source side of an elliptical 2” weld is distorted more than the film side)
If using a one inch diameter ball and the diameter measured on the film is actually 1.2 inches and the film wall measured on the film is 0.500”, the actual wall thickness is 0.416 inches.
Pipe Wall = ( 1” ÷ 1.2” ) X 0.500” Pipe Wall = 0.83 X 0.500”
Pipe Wall = 0.416”
Below is an Excel spreadsheet calculator that you can use.