Pyshield is a package for nuclear medicine departments to calculate the necessary amount of shielding for PET, SPECT, laboratories and therapy rooms.

pip install git+https://github.com/heydude1337/pyshield.git

Python 3.5 or higher must be install on your system.

usage: [-h] [--execute | --getconfig GETCONFIG | --getexample] [--grid | --points] [--config CONFIG] [--log {debug,info,error}]

optional arguments: -h, --help show this help message and exit --execute Do calculations --getconfig GETCONFIG Creates a config file with all options set to default values. --getexample Create example files in current folder --grid Calculate dose maps on grid --points Calculate dose in defined points --config CONFIG Specify config file. config.yml will be loaded by default if present. --log {debug,info,error} Specify log level

pyshield --execute --points

Runs calculations for specified dose points.: barriers.yml: barrier defintions sources.yml: source definitions points.yml: points in which the dose is calculated

pyshield --execute --grid --config myconfig.yml

Calculate dosemaps and override settings from myconfig.yml.
barriers.yml: barrier defintions sources.yml: source definitions

pyshield --getconfig myconfig.yml

Creates myconfig.yml in current folder with all settings set to default.

pyshield --getexample

Create example files in current folder.

By default pyshield tries to load the file config.yml from the current directory. The config file location can be overridden by the --config flag. For a full list of parameters that can be defined in the config file please use pyshield --getconfig myconfig.yml to obtain a file with all settings set to default. Each setting is explained in the comments of this file. If you create your own config file only parameters that have different values than default are needed to be defined.

Most options are fine by default except for the scaling and origin of the floor plan. Create a configuration file or modify the config file as needed:

scale: 3.1415 origin: [100, 100]

The parameter scale is defined in cm/pixel, how big is a pixel in your floor plan image in cm. Origin can be set to an arbritary location in cm. In this case the pixel at 100cm, 100cm will be point 0cm, 0cm.

The floor plan should be supplied as an image and should be called floor_plan.png by default.

A barrier is defined by two points the materials and the thickness of these materials. By default pyshield will load a barriers.yml file from the current folder to load the barrier definitions. An example of three barriers are shown below.

MyLeadWall: Location [cm]: [-50, 50, 50, 50] Material [cm]: Lead: 10 color: [255, 0, 255] MyLeadAndConcreteWall1: Location [cm]: [-50, -50, -50, 50] Material [cm]: Lead: 10 Concrete: 50 Label: LeadConcrete MyLeadAndConcreteWall2: Location [cm]: [50, 50, 50, -50] Material [cm]: Lead: 10 Concrete: 50 Label: LeadConcrete color: red

First each barrier has a name which myst be unique for each barrier. The location of the barrier is specified in cm: [x1, y1, x2, y2]. The barrier is a line between (x1, y1) and (x2, y2). Each barrier can consist of one or more materials. Material thickness is again specified in cm.

Optionally a Label can be specified. Multiple barriers can have the same label. This label is shown in the legend of the images. The walls are drawn by default as blue lines in the output images. The color can be set by the color option in rgb or any valid matplotlib color name'

A source is defined in a single point.

MySource1: Activity [MBq]: 100 Decay correction: true Duration [h]: 1 Isotope: F-18 Location [cm]: [0, 0] Number of exams: 1500 MySource2: Activity [MBq]: 20000 Decay correction: true Duration [h]: 0.5 Isotope: F-18 Location [cm]: [100, 100] Number of exams: 150 Material [cm]: Lead: 1

Most parameters are straight forward. Each source has a name that should be unique as well. Decay correction can be always set to true. It takes the decay of the source during the time the source is present.

Optionally a material can be specified around the source. This can take local shielding ito account which is always present for this source. For example when the source is kept in a lead container.

Points are the locations for which the dose is calculated when using the --points flag.

MyPoint1: Location [cm]: [25, 25] OCCUPANCY_FACTOR: 0.25

Location is the location of the source and an occupancy factor can be defined which is the fraction of time that personnel is present at this location.

Output is generated by default in ./output. An excel file is created, result.xlsx by default and several images are created.

An excel file is generated that contains a table with all properties of the sources. This table is shown on tab 'source_table'. It has the same information as in the sources.yml file.

If the --points flag is used, two additional tables/tabs are created.

sum_table: Shows the total dose in each defined point with and without correction for occupance.

table: Shows intermadiate calculation results for each calculation between a source and a point. For example the total amount of calculated material between MySource1 and MyPoint1 can be found here. This table is useful to check when you are not sure about your calculations.

floor_plan.png shows the shielding as an overlay on the original floor_plan.

sources.png: Shows the location of the defined sources

points.png: Shows the location of the defined points

sum_sources.png Shows a heatmap with iso contours on top of the floor_plan. This file is generated when --grid flag is used.

Settings for showing the results can be changed by editing the visualization.yml file in the pyshield install folder.

Just do:

import pyshield

pyshield.run() or pyshield.run(calculate='grid') or pyshield.run(calculate='points') etc.

Quickly define points on a figure:

pyshield.tools.drawing.points

Quickly define barriers on a figure:

pyshield.tools.drawing.barrier

copy/paste the output to your yml files