<ARTICLE>           5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THERMEDICS
DETECTION INC.'S ANNUAL REPORT ON FORM 10-K FOR THE YEAR ENDED JANUARY 3, 1998
AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<MULTIPLIER>        1,000
       
                              
<PERIOD-TYPE>                                 YEAR
<FISCAL-YEAR-END>                             JAN-03-1998
<PERIOD-END>                                  JAN-03-1998
<CASH>                                                 46,352
<SECURITIES>                                                0
<RECEIVABLES>                                          19,350
<ALLOWANCES>                                            1,127
<INVENTORY>                                            16,819
<CURRENT-ASSETS>                                       87,264
<PP&E>                                                 10,697
<DEPRECIATION>                                          6,686
<TOTAL-ASSETS>                                        148,265
<CURRENT-LIABILITIES>                                  40,919
<BONDS>                                                     0
<PREFERRED-MANDATORY>                                       0
<PREFERRED>                                                 0
<COMMON>                                                1,932
<OTHER-SE>                                            105,414
<TOTAL-LIABILITY-AND-EQUITY>                          148,265
<SALES>                                                89,264
<TOTAL-REVENUES>                                      104,374
<CGS>                                                  38,694
<TOTAL-COSTS>                                          46,395
<OTHER-EXPENSES>                                        9,643
<LOSS-PROVISION>                                          201
<INTEREST-EXPENSE>                                      1,239
<INCOME-PRETAX>                                        20,677
<INCOME-TAX>                                            8,171
<INCOME-CONTINUING>                                    12,506
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<NET-INCOME>                                           12,506
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