diff --git a/README.md b/README.md
index 653f1c7..bdf72da 100644
--- a/README.md
+++ b/README.md
@@ -8,6 +8,16 @@ ArmageDec is a fully GUI-based application, although you can pass the .wsc schem
 
 Note that you can't create a fully new scheme as of now. You need to open an existing .wsc file and start by editing it.
 
+### How to use Mines & Barrels Calculator section
+
+The general scheme options contain "Hazardous Objects Specification" field that combines the selection of hazardous objects (mines and barrels) and their count. To modify this field, you can use the dedicated calculator section to the right of this option:
+
+1. Press the "Decode" button. The Mines and Barrels field should get populated.
+2. Modify the Mines and Barrels field according to your preferences.
+3. Press the "Calculate" button. The result should appear to the left and the "Hazardous Objects Specification" field will be updated accordingly. If necessary, the Mines and Barrels fields will be readjusted according to the values accepted by the algorithm.
+
+Note that if both Mines and Barrels fields are not zero, then their values don't reflect the exact amount of corresponding objects that will appear in the game, only approximates what could happen on the in-game terrain. This is the limitation of the W:A game engine and scheme format itself and not a bug of the editor.
+
 ## Binary builds
 
 It is possible (although absolutely unnecessary) to build ArmageDec as a stand-alone binary. For Windows users, binary builds will be provided along with the source code on the "Releases" tab of the repo.