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 keys 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
Control Interlocking
Solenoid Controlled Key Switches
Time Delay and Voltage Sensing
Power Interlocking
Intermediate Transfer
Metal alloy and stainless steel intermediate transfer devices
Access Control
Door access modules and actuators
Keys & Accessories
Keys and engravings, mounting plates, and lock protection accessories
Are You Looking to Build a Solution from the mGard range?
Click on our “Product Tools” button to design your product today. If you need help or guidance, visit our “How to Buy mGard” page.
Explore our product videos
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.
Explore our product videos
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.
Explore our product videos
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.
Need help?
Our team of experts is always available. Simply click on the button below to get in touch.
Visit these pages to learn more
Fortress Keys – What’s in a Key? What’s in an Engraving?
Door Modules (DM/DMS) for mechanical only access to hazardous spaces.
Key Switch (S, LCU, SCU) – Isolating Hazardous Electrical Energy
Trapped Key interlocking is a tried and tested method of mechanically isolating dangerous machinery and hazardous processes. Find out more about our range of isolation solutions.
Bolt Module (BM, BMS) – Power Interlocking with a Mechanical Bolt
The Bolt Module is a form of Power Interlocking and can be used to prevent mechanical rotation of components used for isolation of pneumatic, hydraulic, or electrical energy.
Pneumatic Trapped Key Isolation (PV PH PL PE PS)
Pneumatic Trapped Key Isolation can be configured alongside electrical isolation to protect against all forms of hazardous energy.
Intermediate Key Transfer – Key Exchange (XM, XMS, J)
Intermediate transfer allows trapped key systems to link points of isolation with access to safeguarded spaces.
Accessories for the Trapped Key Range
Take a closer look at our list of trapped key accessories – lock protection and mounting solutions
Case studies
Using Trapped key in Machinery Safety
Improve machinery safety with trapped key interlocking systems. Fortress Safety has application experts to help with specific machinery safety requirements.
All downloadable assets
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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
Downloads & Technical Info
Drawings & 3D CAD Files
- 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
