About Us

We work to ensure everyone,
everywhere is safe at work

About Us

We work to ensure everyone,
everywhere is safe at work

The global leading group in interlock safety systems

SPS Group are driving process safety practices forward and resolving compliance needs across a wide range of industries.

From our sites in Europe, North America, South America, North Africa and China, the SPS Group companies service a worldwide audience.

Our innovative interlock systems and safety components help to reduce human error, ensure greater risk management and enforce best practice operating procedures are followed on site.

The result? We create a safer, more secure work environment across a multitude of industries, including Energy, Industrial, and Transport.

Headquartered in North Canton, Ohio, USA, KIRK® provide systems and components that remove human error from industrial processes, helping customers better control safety at work.

Established in 1922, Castell offers unrivalled experience in trapped key interlocking. Headquartered in London, U.K., Castell offer distributors worldwide, providing safety systems for industries of all sectors.

Headquartered in Paris, France and serving a worldwide audience, STI has been producing safety devices since 1894. Their products include locks and switches for control circuits, switchgear and access points.

SPS is a part of Halma plc, a global group of life-saving technology companies

Halma is a global group of life-saving technology companies. Named one of Britain’s Most Admired Companies in 2019, we provide innovative solutions to many of the key problems facing the world today. Halma’s purpose is to grow a safer, cleaner, healthier future for everyone, every day. Our purpose drives every business decisions we make and ensures we are working towards it every day. SPS is very proud to be a part of the Halma group. Our drive to create a safer and secure work environment is completely aligned with Halma’s purpose.

SPS in Numbers

A proud history of mark leadership

With a proud heritage stretching back to 1894, our companies are at the forefront of industry developments.

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Customers in more than

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Leaning on

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125 years

expertise in safety systems

Establishment dates of SPS Companies:

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Our leadership

SPS Group is guided by some of the world’s leading safety experts

Our leadership team brings together some of the most knowledgeable experts from the safety field, including representatives from all three companies in the group.