**EXHIBIT31.2**

 

**CERTIFICATION OF CHIEF FINANCIAL OFFICER OF THE 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 Form 10-Q of Dynamex Inc.;

 

2.                                       Based on my knowledge, this report does not contain any untrue statementsof a material fact or omit to state a material fact necessary to make thestatements made, in light of the circumstances under which such statements weremade, not misleading with respect to the period covered by this report;

 

3.                                       Based on my knowledge, the financial statements, and other financialinformation included in this report, fairly present in all material respectsthe financial condition, results of operations and cash flows of Dynamex Inc.as of, and for, the periods presented in this report.

 

4.                                       The registrant’sother certifying officer and I are responsible for establishing and maintainingdisclosure controls and procedures (as defined in Exchange Act Rules 13a-14 and15d-14) for the registrant and we have:

a.                                       Designed suchcontrols and procedures, or caused such disclosure controls and procedures tobe designed under our supervision, to ensure that material information relatingto the registrant, including its consolidated subsidiaries, is made known to usby others within those entities, particularly during the period in which thisreport is being prepared;

b.                                      Evaluated theeffectiveness 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.                                       Disclosed inthis 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.                                       The registrant’sother certifying officer and I have disclosed, based on our most recentevaluation of internal control over financial reporting, to the registrant’sauditors and the audit committee of registrant’s board of directors;

a.                                       All significantdeficiencies and material weaknesses in the design or operation of internalcontrols which could adversely affect the registrant’s ability to record,process, summarize and report financial information; and

b.                                      Any fraud,whether or not material, that involves management or other employees who have asignificant role in the registrant’s internal controls over financialreporting.

 

 

 
| Date:    March  9, 2005 |                                       |
|----------------------------------------|--------------------------------------------|
|                                   |                                       |
|                                   |                                       |
|                                   |                                       |
| /s/ RAY E. SCHMITZ                     |                                       |
| Name:                                  | Ray E. Schmitz                             |
| Title:                                 | Vice President and Chief Financial Officer |
|                                        |                                            |  |

 

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