Our History
Each of our brands have been at the forefront of trapped key interlocking for over 100 years.
Take a look at our history and see how what started as a simple design to protect people and assets, turned into a globally successful safety solutions business.
2023
Sentric announces it has acquired Zonegreen. Headquartered in Sheffield, United Kingdom, Zonegreen develops technologies, software and services that make working in rail depots safer and more efficient. Zonegreen’s products are used by rail customers across the UK, Ireland and Australia.
2022
The global SPS formed in 2016, becomes Sentric Group, consisting of three sister companies Kirk in the US, STI in France and Castell in the UK. Our mission is to unite the world’s leading brands, product innovations, and experts to protect people in safety by mitigating the risk caused by human error. As Sentric, we share Purpose, Vision, Mission, and Values which bring unity, clarity and direction to everything we do.
2022
Castell celebrates its 100th anniversary.
2019
Castell becomes ISO 45001 certified.
2017
Serv Trayvou Interverrouillage and Castell develop a digital solution for truck key management integrating Salvo and SKM together in 2017.
2016
The global leading group for interlock safety systems was formed back in 2016. It consists of three market-leading businesses, Kirk, Castell and STI, combining the expertise and high quality products of the three brands.
2014
In September 2014, Kirk moved operations and manufacturing to North Canton, OH, USA.
2012
Castell celebrates its 90th anniversary.
2012
Castell wins the Halma Manufacturing Excellence Award.
2011
In 2011 Kirk Key Interlock Company LLC was purchased by the holdings company Halma plc.
2009
In 2009, STI and HF Sécurité merge under the name Serv Trayvou Interverrouillage becoming the main safety interlocks company in France for the Industry & Manufacturing, Energy and Transport sectors.
2008
STI launches the very first RFID access management system SKM and takes a step into the digital world and industry.
2005
Launch of new product range Salvo.
1999
In December of 1999, Kirk Key Interlock Company LLC separated from ABB and was completely independent, moving operations to Massillon, Ohio, USA.
1999
Castell purchases new product range Mistura.
1994
STI is certified ISO9001-2000, a must-have for quality assurance.
1990
Castell UK becomes ISO 9001 certified.
1987
Halma Group buys Trayvou and merges the French companies in 1987.
1983
Castell purchases Iso-Lok lockout tagout product range.
1974
UK Health and Safety at Work Act.
1971
Halma Investments Limited purchases Castell Locks Limited.
1962
In 1962, Halma Group buys SERV.
1961
Mr Barillet leaves Trayvou to establish the company SERV in 1961, the trapped key Interlocking business.
1933
Castell granted improvement to padlocks patent (patent number GB430168).
1932
In 1932, KIRK® trapped key interlocks were manufactured in Greensburg, Pennsylvania in the USA, as part of the Railway & Industrial Engineering Company which held the patent filed by R.L. Kirk.
1931
R.L. Kirk filed for his first patent “Safety Interlock for Electrical and Mechanical Equipment and Systems” in 1931 and Kirk became an authority in electrical safety.
1922
James Harry Castell establishes ‘Castell Locks.’
1921
Castell’s oldest recorded order placed by leading UK engineering and heavy industrial company
1920
James Harry Castell patents ‘Castell’ figure interlocking system to protect people during the electrification period in London.
1900
At the 1900 World Exposition in Paris, Mr Bouré triumphed with a gold award for his invention.
1895
In 1895, Trayvou manufacturers interlocking devices for the manufacturing industry and the railway industry.
1894
For the first time in the world, an interlocking system was designed in 1894.
1893
In 1893, Paul Bouré creates engagement lock devices to ensure train traffic safety.