What is mGard?


mGard is Fortress range of mechanical trapped key interlocks. 3rd party approved, products are suitable for use up to PLe/Cat. 4 or SIL 3.


Trapped key interlocking can be used to enforce complex safety sequences, particularly where multiple energy sources (e.g., electrical, pneumatic, hydraulic) are involved.


Mechanical interlocks eliminate most of the electrical wiring associated with other types of interlocks, making mGard cost effective and easy to install and maintain.


Fortress keeps a database of all keys and locks and their locations to prevent the unintentional duplication of key codes on site.



Why choose mGard?

Why choose mGard?

Explore the Mechanical Trapped Key Range

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How to buy mGard

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Fortress Product Feature - mGard Trapped Key Range

Overview video of the main features of the mGard range. Electrical, pneumatic, hydraulic, and kinetic energy sources can all be interlocked using mGard products, and typically at a fraction of the cost of alternative solutions.


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What is Trapped Key Interlocking?

Fortress mGard products are designed, tested and 3rd party approved for use up to Category 4/PLe. A single Fortress interlock does not require additional safety components added to meet PLe.

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How trapped key interlocking works

This video showcases how you can integrate a simple Trapped Key System via our mGard Range of Trapped Key Interlocks.

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  • Select from our range of high-coded compact yet robust interlocks here.
  • Use our Datasheets / drawing generators to create technical files, datasheets, and CAD for your selected product.
  • Convert your unique ITM number into a Fortress part number using our Reference tool
  • Calculate the performance level of your unique safety system using our SISTEMA library
  • Click here for more Fortress Product tools