-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 PdaWqDniTuhv62XCnSIOUN40d/FRrxX+v/UWeMwecH/iQv7BNZH9DL45s+TaZOi0
 Vb2p92BXorwnYq1rGtYOlQ==

<SEC-DOCUMENT>0001181431-08-045875.txt : 20080804
<SEC-HEADER>0001181431-08-045875.hdr.sgml : 20080804
<ACCEPTANCE-DATETIME>20080804160250
ACCESSION NUMBER:		0001181431-08-045875
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080804
FILED AS OF DATE:		20080804
DATE AS OF CHANGE:		20080804

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			STERIS CORP
		CENTRAL INDEX KEY:			0000815065
		STANDARD INDUSTRIAL CLASSIFICATION:	ORTHOPEDIC, PROSTHETIC & SURGICAL APPLIANCES & SUPPLIES [3842]
		IRS NUMBER:				341482024
		STATE OF INCORPORATION:			OH
		FISCAL YEAR END:			0331

	BUSINESS ADDRESS:	
		STREET 1:		5960 HEISLEY RD
		CITY:			MENTOR
		STATE:			OH
		ZIP:			44060
		BUSINESS PHONE:		4403542600

	MAIL ADDRESS:	
		STREET 1:		5960 HEISLEY ROAD
		CITY:			MENTOR
		STATE:			OH
		ZIP:			44060

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			AAMOTH WILLIAM L
		CENTRAL INDEX KEY:			0001236375

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-14643
		FILM NUMBER:		08988121

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		4403927169

	MAIL ADDRESS:	
		STREET 1:		STERIS CORP
		STREET 2:		5960 HEISLEY ROAD
		CITY:			MENTOR
		STATE:			OH
		ZIP:			44060
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>rrd214872.xml
<DESCRIPTION>BILL AAMOTH FORM 4 FILING
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-08-04</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000815065</issuerCik>
        <issuerName>STERIS CORP</issuerName>
        <issuerTradingSymbol>STE</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001236375</rptOwnerCik>
            <rptOwnerName>AAMOTH WILLIAM L</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>5960 HEISLEY ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>MENTOR</rptOwnerCity>
            <rptOwnerState>OH</rptOwnerState>
            <rptOwnerZipCode>44060</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>V P - Corporate Treasurer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Shares, No Par Value</value>
            </securityTitle>
            <transactionDate>
                <value>2008-08-04</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>7500</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>22.58</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>12700</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Shares, No Par Value</value>
            </securityTitle>
            <transactionDate>
                <value>2008-08-04</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>7500</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>35.4581</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>5200</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Employee Stock Option Exercise</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>22.58</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2008-08-04</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>7500</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2013-05-23</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Shares, No Par Value</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>7500</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>4500</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">4,500 of these Common Shares are restricted. The restrictions on these Common Shares lapse as follows: 1,400 on September 7, 2009, 1,500 on July 27, 2010, and 1,600 on May 23, 2011.</footnote>
        <footnote id="F2">These options became exercisable as follows: 3,000 on April 23, 2004, 3,000 on April 23, 2005 and 1,500 on April 23, 2006.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Dennis P. Patton, Authorized Representative under Power of Attorney</signatureName>
        <signatureDate>2008-08-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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