<TABLE> <S> <C>

<PAGE>
<ARTICLE> 5
<LEGEND>
This schedule contains summary financial information extracted from The
Consolidated Balance Sheet as of June 30, 1999 and December 31, 1998 and the
Statement of Operations for the three and six months ended June 30, 1999 and
June 30, 1998 and is qualified in its entirety by reference to such financial
statements.
</LEGEND>
<CIK> 0000884269
<NAME> ALPHA PRO TECH LTD.
<MULTIPLIER> 1,000

<S>                             <C>                     <C>
<PERIOD-TYPE>                   3-MOS                   6-MOS
<FISCAL-YEAR-END>                          DEC-31-1999             DEC-31-1999
<PERIOD-START>                             APR-01-1999             JAN-01-1999
<PERIOD-END>                               JUN-30-1999             JUN-30-1999
<CASH>                                             486                     486
<SECURITIES>                                         0                       0
<RECEIVABLES>                                    3,816                   3,816
<ALLOWANCES>                                        48                      48
<INVENTORY>                                      3,284                   3,284
<CURRENT-ASSETS>                                 7,781                   7,781
<PP&E>                                           3,739                   3,739
<DEPRECIATION>                                   1,639                   1,639
<TOTAL-ASSETS>                                  10,446                  10,446
<CURRENT-LIABILITIES>                            3,625                   3,625
<BONDS>                                              0                       0
<PREFERRED-MANDATORY>                                0                       0
<PREFERRED>                                          0                       0
<COMMON>                                           241                     241
<OTHER-SE>                                      24,338                  24,338
<TOTAL-LIABILITY-AND-EQUITY>                    10,446                  10,446
<SALES>                                          5,222                   9,712
<TOTAL-REVENUES>                                 5,222                   9,712
<CGS>                                            3,164                   5,759
<TOTAL-COSTS>                                    1,739                   3,322
<OTHER-EXPENSES>                                     0                       0
<LOSS-PROVISION>                                     0                       0
<INTEREST-EXPENSE>                                  39                      80
<INCOME-PRETAX>                                    280                     551
<INCOME-TAX>                                         0                       0
<INCOME-CONTINUING>                                280                     551
<DISCONTINUED>                                       0                       0
<EXTRAORDINARY>                                      0                       0
<CHANGES>                                            0                       0
<NET-INCOME>                                       280                     551
<EPS-BASIC>                                        .01                     .02
<EPS-DILUTED>                                      .01                     .02


</TABLE>