Exhibit 99.1

STERIS CORPORATION

NEWS ANNOUNCEMENT

FOR IMMEDIATE RELEASE

STERIS CORPORATION ANNOUNCES FISCAL 2011 FIRST QUARTER RESULTS

Mentor, Ohio (August 3, 2010) - STERIS Corporation (NYSE: STE) today announced financial results for its fiscal 2011 first quarter ended June 30, 2010. During the first quarter, the Company recorded the previously announced liability related to the SYSTEM 1 Rebate Program. Of the $110 million pre-tax amount recorded, $102 million is attributable to the Customer Rebate portion of the Program and was recorded as a reduction of revenues, and $8 million is attributable to the disposal of the SYSTEM 1 units to be returned and was recorded as an increase in cost of revenues.

In order to provide meaningful comparative analysis, the fiscal 2011 financial information provided in this press release excludes the $110 million pre-tax impact of the SYSTEM 1 Rebate Program unless otherwise noted. Please refer to the attached schedules for additional information, including reconciliations from these “non-GAAP financial measures” to as reported results.

Fiscal 2011 first quarter revenues were $291.3 million compared with $283.5 million in the first quarter of fiscal 2010, an increase of 3%. Operating profit increased 10% to $47.0 million, or 16.1% of revenues, compared with $42.9 million, or 15.1% of revenues in the first quarter of fiscal 2010. Fiscal 2011 first quarter net income was $28.0 million, or $0.46 per diluted share, compared with net income of $25.5 million, or $0.43 per diluted share, in the first quarter of fiscal 2010.

“Early indications are that more Customers may use the SYSTEM 1 Rebate to purchase SYSTEM 1E units than we originally anticipated, which has increased our original Rebate Program estimate,” said Walt Rosebrough, President and Chief Executive Officer of STERIS. “While it is still too early to predict what the total SYSTEM 1E demand will be, we are optimistic about Customer response to this new product. We continue to believe we will be able to manufacture 4,000 to 6,000 units this fiscal year, with shipments beginning in the next few months.”

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Segment Results

Healthcare revenues in the quarter were $206.1 million compared with $200.6 million in the first quarter of fiscal 2010, an increase of 3%. Double digit growth in capital equipment was somewhat offset by declines in consumables and service. Capital equipment revenue grew 16%, reflecting increases in most major product categories. Consumable revenue declined 9%, due to reductions in S20 volumes and lower H1N1 product sales as compared to the prior year. Operating income was flat with the prior year at $32.1 million primarily due to lower S20 volumes.

Life Sciences first quarter revenues were $46.6 million compared with $46.1 million in the first quarter of fiscal 2010, an increase of 1%. Strength in consumables and service was offset by a decline in capital equipment. Life Sciences operating income was $6.3 million, an increase of 32% compared with the prior year, driven by product mix and overall operating efficiencies.

Fiscal 2011 first quarter revenues for Isomedix Services were $37.7 million compared with $35.4 million in the same period last year, an increase of 6%. Revenues benefitted from an improvement in demand from core medical device Customers. Operating income was $10.6 million in the quarter compared with $8.3 million in the first quarter of last year due to the increased revenues.

As Reported Results

Reported results for the first quarter of fiscal 2011 were revenues of $189.0 million, operating loss of $63.0 million and a net loss of $45.2 million. Please refer to the attached schedules for additional information.

Cash Flow

Net cash provided by operations for the first quarter of fiscal 2011 was $29.6 million, compared with $32.6 million in the same period last year. Free cash flow (see note 1) for the first quarter of fiscal 2011 was $17.3 million, compared with $24.4 million in the prior year quarter. The decline in free cash flow was driven by increased working capital requirements and higher capital spending levels.

Quarterly Dividend Increased

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The Company also announced today that STERIS’s Board of Directors has authorized a four cent increase in its quarterly dividend to $0.15 per common share. The dividend is payable September 21, 2010 to shareholders of record at the close of business on August 24, 2010.

Outlook

The Company’s outlook is unchanged for the full fiscal year, with revenue growth of approximately 5%, and earnings per diluted share in the range of $2.00 to $2.30. Refer to the earnings announcement dated May 6, 2010 for the detailed full year outlook and other assumptions.

Conference Call

In conjunction with this release, STERIS Corporation management will host a conference call today at 10:00 a.m. Eastern time. The conference call can be heard live over the Internet at www.steris-ir.com or via phone by dialing 1-800-369-8428 in the United States and Canada, and 1-773-799-3378 internationally, then referencing the password “STERIS”.

For those unable to listen to the conference call live, a replay will be available from 12:00 p.m. Eastern time on August 3, 2010, until 5:00 p.m. Eastern time on August 17, 2010, either over the Internet at www.steris-ir.com or via phone by calling 1-866-415-3316 in the United States and Canada, and 1-203-369-0695 internationally.

About STERIS

The mission of STERIS Corporation is to provide a healthier today and safer tomorrow through knowledgeable people and innovative infection prevention, decontamination and health science technologies, products and services. The Company has approximately 5,000 dedicated employees around the world working together to supply a broad array of solutions by offering a combination of equipment, consumables and services to healthcare, pharmaceutical, industrial and government Customers. The Company is listed on the New York Stock Exchange under the symbol STE. For more information, visit www.steris.com.

Contact: Julie Winter, Director, Investor Relations at 440-392-7245.

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future growth opportunities, repurchase common shares, and pay cash dividends. Free cash flow is defined as cash flows from operating activities less purchases of property, plant, equipment and intangibles, net, plus proceeds from the sale of property, plant, equipment and intangibles. STERIS’s calculation of free cash flow may vary from other companies.

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This news release and the referenced conference call may contain statements concerning certain trends, expectations, forecasts, estimates, or other forward-looking information affecting or relating to the Company or its industry or products that are intended to qualify for the protections afforded “forward-looking statements” under the Private Securities Litigation Reform Act of 1995 and other laws and regulations. Forward-looking statements speak only as to the date of this report, and may be identified by the use of forward-looking terms such as “may,” “will,” “expects,” “believes,” “anticipates,” “plans,” “estimates,” “projects,” “targets,” “forecasts,” “outlook,” “potential,” “confidence,” “improve,” “optimistic,” “comfortable,” “trend”, and “seeks,” or the negative of such terms or other variations on such terms or comparable terminology. Many important factors could cause actual results to differ materially from those in the forward-looking statements including, without limitation, disruption of production or supplies, changes in market conditions, political events, pending or future claims or litigation, competitive factors, technology advances, actions of regulatory agencies, and changes in laws, government regulations, labeling or product approvals, or the application or interpretation thereof. Other risk factors are described in the Company’s Form 10-K and other securities filings. Many of these important factors are outside STERIS’s control. No assurances can be provided as to any outcome from litigation, regulatory action, administrative proceedings, government investigations, warning letters, consent decree, rebate program, transition, cost reductions, business strategies, earnings and revenue trends, expense reduction or other future financial results. Reference to the consent decree, transition, rebate program, or products are summaries only and do not alter or modify the specific terms of the decree, program or product clearance or literature. Unless legally required, the Company does not undertake to update or revise any forward-looking statements even if events make clear that any projected results, express or implied, will not be realized. Other potential risks and uncertainties that could cause actual results to differ materially from those in the forward-looking statements include, without limitation, (a) the potential for increased pressure on pricing that leads to erosion of profit margins, (b) the possibility that market demand will not develop for new technologies, products or applications, or the Company’s rebate program, transition plan, or other business initiatives will take longer, cost more or produce lower benefits than anticipated, (c) the possibility that application of or compliance with laws, court rulings, certifications, regulations, regulatory actions, including without limitation previously disclosed FDA warning letters, government investigations, the December 3, 2009 FDA notice, the April 20, 2010 consent decree and related transition plan, or other requirements or standards, may delay, limit or prevent new product introductions or the production and marketing of existing products, or otherwise affect Company performance, results, or value, (d) the potential of international unrest or effects of fluctuations in currencies, tax assessments or rates, raw material costs, benefit or retirement plan costs, or other regulatory compliance costs, (e) the possibility of reduced demand, or reductions in the rate of growth in demand, for the Company’s products and services, (f) the possibility that anticipated cost savings or other results may not be achieved, or that transition, labor, competition, timing, execution, regulatory, governmental, or other issues or risks associated with the matters described in this release or the operation of the Company’s business, may adversely impact Company performance, results, or value, (g) the effect of the contraction in credit availability, as well as the ability of our customers and suppliers to adequately access the credit markets when needed, and (h) those risks described in our Annual Report on Form 10-K for the year ended March 31, 2010.

STERIS Corporation

Consolidated Condensed Statements of Operations

(In thousands, except per share data)

STERIS Corporation

Income Reconciliation

(In thousands, except per share data)

The following table presents financial measures which are considered to be "non-GAAP financial measures" under Securities Exchange Commission rules. The Company has referred to results of operations excluding the SYSTEM 1 Rebate Program and related disposal costs to provide meaningful comparative analysis between the periods.

STERIS Corporation

Segment Data & Income Analysis

(In thousands)

The following table presents financial measures which are considered to be “non-GAAP financial measures” under Securities Exchange Commission rules. The Company has referred to results of operations excluding the SYSTEM 1 Rebate Program and related disposal costs to provide meaningful comparative analysis between the periods.

STERIS Corporation

Consolidated Condensed Statements of Cash Flows

(In thousands)

The following table presents a financial measure which is considered to be "non-GAAP financial measures" under Securities Exchange Commission rules. Free cash flow is defined by the Company as cash flows from operating activities less purchases of property, plant, equipment and intangibles, net (capital expenditures) plus proceeds from the sale of property, plant, equipment and intangibles. The Company uses free cash flow as a measure to gauge its ability to fund future growth opportunities, repurchase common shares, and pay cash dividends. STERIS's calculation of free cash flow may vary from other companies.

STERIS Corporation

Unaudited Supplemental Financial Data - Excluding SYSTEM 1 Rebate Program

First Quarter Fiscal 2011

As of June 30, 2010

This supplemental data is consistent with publicly disclosed information provided in quarterly conference calls, earnings releases and SEC filings, and is subject to all definitions, precautions and limitations contained in those disclosures. Please see the Company's most recent 10-K for definitions (and reconciliation where appropriate) of backlog, free cash flow and net debt.