Appointment of Non-Executive Directors

DIPLOMA PLC

12 CHARTERHOUSE SQUARE, LONDON EC1M 6AX

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FOR IMMEDIATE RELEASE

30 May 2013

DIPLOMA PLC

APPOINTMENT OF NON-EXECUTIVE DIRECTORS

Diploma PLC, the international group of specialised businesses supplying technical products and services, announces the appointment of John Nicholas and Charles Packshaw as Non-Executive Directors of the Board of Diploma PLC with effect from 1 June 2013.

These appointments follow the decisions of John Matthews and Ian Grice to retire from the Board at the conclusion of the Board meeting on 26 September 2013.

John Nicholas is currently a Non-Executive Director of Mondi plc, Hunting PLC and Rotork PLC, having previously been Group Finance Director of Tate & Lyle plc and Kidde plc. John is also a member of the Financial Reporting Review Panel and a Fellow of the Association of Chartered Certified Accountants.

Charles Packshaw is the Head of UK Advisory and a Managing Director in HSBC's Global Banking business. He has nearly thirty years City experience, including 18 years at Lazard in London, where he was Head of Corporate Finance, prior to joining HSBC in 2002. He is also a Chartered Engineer.

Commenting on the two new appointments, John Rennocks, Chairman of Diploma PLC said:

"I am delighted to welcome John and Charles to the Board with all of their skills and experience, as we continue to develop Diploma through a combination of organic investment and acquisition.

I also wish to thank both John and Ian for the wise counsel and guidance they have provided to the Board over many years, which has contributed to the significant success of the Group."

A further announcement regarding appointments to the Board's principal sub-Committees will be made later in the financial year. There are no disclosures required under paragraph 9.6.13(2)-(6) of the Listing Rules of the UK Listing Authority.