Holding(s) in Company

Porvair PLC
03 August 2005


LETTER TO:  RNS

Section 198 Companies Act 1985 - notifiable interests

We were advised today that:

Schroder Investment Management Limited has an interest in 8,868,035 shares in
Porvair plc, which are held in portfolios managed by them on a discretionary
basis for clients under investment management agreements. This interest
represents 24.10% of the Company's issued share capital.

From:      C. P. Tyler (Company Secretary)


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