Exhibit 99.1

STERIS CORPORATION

NEWS ANNOUNCEMENT

FOR IMMEDIATE RELEASE

STERIS CORPORATION ANNOUNCES

FISCAL 2006 THIRD QUARTER RESULTS

Mentor, Ohio (January 31, 2006) - STERIS Corporation (NYSE: STE) today announced financial results for its fiscal 2006 third quarter ended December 31, 2005. Fiscal 2006 third quarter revenues increased 5% to $287.5 million, compared with $273.8 million in the third quarter of fiscal 2005, driven by growth in all three segments. Operating income was $39.1 million compared with $38.6 million in the fiscal 2005 quarter.

Net income was $28.1 million, or $0.41 per diluted share in the third quarter of fiscal 2006, compared with net income of $24.5 million, or $0.35 per diluted share in the same period last year. During the third quarter, the Company completed the sale, subject to post closing adjustments, of its freeze dryer product line in the Life Sciences segment, which is presented as a discontinued operation. Included in net income is an after-tax gain on the sale of $5.2 million, and a loss of $0.3 million from discontinued operations. Net income from continuing operations was $23.2 million, or $0.34 per diluted share, compared with net income from continuing operations of $23.6 million, or $0.34 per diluted share in the third quarter of fiscal 2005.

“We are pleased with the solid performance of all three of the Company’s segments after a difficult first half. The actions taken in Life Sciences to date have resulted in strengthened segment performance as we witnessed increased revenue, improved backlog levels, and an increase in profitability for the quarter. We remain committed to ongoing improvement in that segment as we continue to take actions to improve our cost structure and drive growth,” said Les C. Vinney, STERIS’s president and chief executive officer. “Similarly, the previously announced decision to transfer our Erie, Pennsylvania manufacturing operations to Mexico reflects the focus of our efforts within the Healthcare segment to strengthen our cost position to support future growth and international expansion.”

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Segment Results

Healthcare revenues for the third quarter increased 3% to $203.7 million, primarily as a result of revenues associated with acquired businesses, including strong U.S. sales of the C-Max surgical table. The Healthcare segment’s base capital equipment offering was impacted by market softness in North America as fluctuations in hospital spending reduced demand for large capital projects. Healthcare segment operating profit was $33.1 million for the quarter, compared with $34.6 million in the third quarter of last year. The decline in operating profit is primarily attributable to an increase in operating expenses largely related to growth initiatives.

Life Sciences third quarter revenues increased 2% to $52.7 million compared with $51.6 million in the third quarter of fiscal 2005. All amounts have been adjusted to reflect the sale of the freeze dryer product line, the results of which have been eliminated from both periods. The increase in revenues reflects improved demand in North America, as the Company began to regain momentum in its core product lines. This was partially offset by a revenue decline in Europe. Life Sciences recorded operating profit of $0.7 million in the quarter, compared with a loss of $0.5 million in the same period last year, reflecting improved mix from higher margin recurring revenues and operating expense control initiatives.

Third quarter revenues for Isomedix Services increased 25% to $31.2 million compared with the prior year third quarter, primarily reflecting revenues associated with the acquisition of certain assets of the Cosmed Group. Base processing revenues were flat with last year’s quarter when the Company was able to secure business from a temporary reduction in industry capacity. Segment operating profit was $5.2 million compared with $4.6 million in the prior year quarter. Lower segment operating margin rate primarily reflected a change in revenue mix and a return to normal capacity levels within the industry.

Cash Flow

Cash provided by operations for the first nine months of fiscal 2006 was $99.4 million, compared with $96.0 million in the same period last year. Free cash flow (see note below) was $65.0 million, compared with free cash flow of $57.2 million in the first nine months of fiscal

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2005, primarily reflecting reduced capital expenditures. Capital expenditures for the first nine months of fiscal 2006 were $34.3 million, compared with $38.8 million in the same period last year.

During the quarter, the Company repurchased 954,375 shares of its common stock at an average price of $26.09 per common share for a total cash amount of $24.9 million. On January 25, 2006, the Company’s Board of Directors approved a new share repurchase authorization for up to 3 million shares, replacing the previous authorization, under which approximately 150,000 shares remained.

Outlook

In the fourth quarter of fiscal 2006, STERIS anticipates incurring pre-tax costs of approximately $30 million, primarily for non-cash expenses related to asset write downs, and accelerated recognition of pension and retiree medical benefits related to the transfer of manufacturing operations from Erie, Pennsylvania to Mexico. Also included in that estimate are expenses related to certain cost reduction initiatives within the ongoing operations of the Life Sciences and Healthcare segments. In total, the Company anticipates that these actions will impact diluted earnings per share by approximately $0.27 in the fourth quarter of fiscal 2006.

Based upon current results and anticipated trends for the remainder of the fiscal year, the Company expects revenue growth to be in the range of 5% to 6% for the fourth quarter, and in the range of 6% to 7% for the full fiscal year. The Company also anticipates that earnings per diluted share will be in the range of $0.16 to $0.18 for the fourth quarter, and in the range of $1.05 to $1.07, including discontinued operations, for the full fiscal year. Earnings for both periods include the $0.27 per diluted share impact of the expenses referenced above.

Conference Call

In conjunction with this press 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 1-888-392-9976 in the United States and Canada, and 1-517-645-6486 internationally, then referencing the password “STERIS” and the conference leader’s name, “Aidan Gormley.”

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For those unable to listen to the conference call live, a replay will be available from 12:00 p.m. Eastern time on January 31, 2006, until 5:00 p.m. Eastern time on February 14, 2006, either over the Internet at www.steris-ir.com or via phone by calling 1-800-756-3940 in the United States and Canada, and 1-402-998-0796 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’s more than 5,000 dedicated employees around the world work 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.

Note: Free cash flow is a non-GAAP number used by the Company as a measure to gauge its ability to invest for growth. Free cash flow is defined as operating cash flow less purchases of property, plant, equipment, and intangibles, net (capital expenditures). STERIS’s calculation of free cash flow may vary from other companies.

Contact: Aidan Gormley, Senior Director, Corporate Communications and Investor Relations at 440-392-7607.

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This news release and the conference call referenced here may contain statements concerning certain trends, expectations, forecasts, estimates, or other forward-looking information affecting or relating to the Company or its industry 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,” and “seeks,” or the negative of such terms or other variations on such terms or comparable terminology. Many important factors could

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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, and changes in government regulations 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 future financial results. 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 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, regulations, certifications or other requirements or standards may delay or prevent new product introductions, affect 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 foreign currencies of countries where the Company does a sizeable amount of business, (e) the possibility of reduced demand, or reductions in the rate of growth in demand, for the Company’s products and services, and (f) the possibility that anticipated cost savings 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 may adversely impact Company performance, results, or value.

STERIS Corporation

Consolidated Condensed Statements of Income

(In thousands, except per share data)

STERIS Corporation

Segment Data

(In thousands)

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). Free cash flow is a non-GAAP figure used by the Company as a measure to gauge its ability to invest for growth. STERIS’s calculation of free cash flow may vary from other companies.