**EXHIBIT 31.2**

 

**CERTIFICATION OF CHIEF FINANCIAL OFFICER OFTHE REGISTRANT,PURSUANT TO 17 CFR 240.13a – 14(a) OR 17 CFR 240.15d – 14(a)**

 

I, Ray E. Schmitz, certify that:

 

1.                                       I have reviewed this quarterly report on Form10-Q of Dynamex Inc.;

 

2.                                       Based on my knowledge, this report does notcontain any untrue statements of a material fact or omit to state a materialfact necessary to make the statements made, in light of the circumstances underwhich such statements were made, not misleading with respect to the periodcovered by this report;

 

3.                                       Based on my knowledge, the financial statements,and other financial information included in this report, fairly present in allmaterial respects the financial condition, results of operations and cash flowsof Dynamex Inc. as of, and for, the periods presented in this report.

 

4.                                       Theregistrant’s other certifying officer and I are responsible for establishingand maintaining disclosure controls and procedures (as defined in Exchange ActRules 13a-14 and 15d-14) for the registrant and we have:

 

a.                                       Designedsuch controls and procedures, or caused such disclosure controls and proceduresto be designed under our supervision, to ensure that material informationrelating to the registrant, including its consolidated subsidiaries, is madeknown to us by others within those entities, particularly during the period inwhich this report is being prepared;

 

b.                                      Evaluatedthe effectiveness of the registrant’s disclosure controls and procedures andpresented in this report our conclusions about the effectiveness of thedisclosure controls and procedures, as of the end of the period covered by thisreport based on such evaluation, and

 

c.                                       Disclosedin this report any change in the registrant’s internal control over financialreporting that occurred during the registrant’s most recent fiscal quarter thathas materially affected, or is reasonably likely to materially affect, theregistrant’s internal control over financial reporting;

 

5.                                       Theregistrant’s other certifying officer and I have disclosed, based on our mostrecent evaluation of internal control over financial reporting, to theregistrant’s auditors and the audit committee of registrant’s board ofdirectors;

 

a.                                       Allsignificant deficiencies and material weaknesses in the design or operation ofinternal controls which could adversely affect the registrant’s ability torecord, process, summarize and report financial information; and

 

b.                                      Anyfraud, whether or not material, that involves management or other employees whohave a significant role in the registrant’s internal controls over financialreporting.

 

 

Date:     December6, 2004

 

 
| /s/ RAY E. SCHMITZ |                                       |
|--------------------|--------------------------------------------|
| Name:              | Ray E. Schmitz                             |
| Title:             | Vice President and Chief Financial Officer |
|                    |                                            |  |

 

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