Debra Miles, Relator, vs. Koch Refining Company, LP, Respondent,Commissioner of Economic Security, Respondent.

may not be cited except as provided by

Minn. Stat. § 480 A. 08, subd. 3 (1996).

 STATE OF MINNESOTA

 IN COURT OF APPEALS

  C5-97-1508

Debra Miles,

Relator,

vs.

Koch Refining Company, LP,

Respondent,

Commissioner of Economic Security,

Respondent.

,Filed March 10, 1998

 Affirmed

 Kalitowski, Judge

Department of Economic Security

File No. 2896UC97

Debra Miles, 1423 9th Avenue South, South St. Paul, MN 55075-3311 (pro se relator)

Kent E. Todd, 390 North Robert Street, St. Paul, MN 55101 (for respondent Commissioner of Economic Security)

Considered and decided by Kalitowski, Presiding Judge, Davies, Judge, and Foley, Judge.*

*Retired judge of the Minnesota Court of Appeals, serving by appointment pursuant to Minn. Const. art. VI, § 10.

 U N P U B L I S H E D O P I N I O N

 KALITOWSKI, Judge

Relator Debra Miles challenges the decision of the Commissioner of Economic Security's representative that she was disqualified from receiving reemployment insurance benefits because she was terminated by Koch Refining Co. (KRC) for misconduct. We affirm.

 D E C I S I O N

The findings of the commissioner's representative must "be viewed in the light most favorable to the decision, and if there is evidence reasonably tending to sustain them, they will not be disturbed." White v. Metropolitan Med. Ctr., 332 N.W.2d 25, 26 (Minn. 1983). Ultimately, the determination of whether the commissioner's representative properly disqualified relator "from receiving reemployment insurance benefits, however, is a question of law upon which this court remains `free to exercise its independent judgment.'" Lolling v. Midwest Patrol, 545 N.W.2d 372, 377 (Minn. 1996) (quoting Ress v. Abbott Northwestern Hosp., Inc., 448 N.W.2d 519, 523 (Minn. 1989)).

Under the Minnesota Reemployment Insurance statute, an employee who is discharged for misconduct is disqualified from receiving reemployment insurance benefits. Minn. Stat. § 268.09, subd. 1(b) (1996). Misconduct

"is limited to conduct evincing such wilful or wanton disregard of an employer's interests as is found in deliberate violations or disregard of standards of behavior which the employer has the right to expect of his employee, or in carelessness or negligence of such degree or recurrence as to manifest equal culpability, wrongful intent or evil design, or to show an intentional and substantial disregard of the employer's interests or of the employee's duties and obligations to his employer. On the other hand, mere inefficiency, unsatisfactory conduct, failure in good performance as a result of inability or incapacity, inadvertencies, or ordinary negligence in isolated instances, or good faith errors in judgment or discretion are not to be deemed `misconduct.'"

 Tilseth v. Midwest Lumber Co., 295 Minn. 372, 374-75, 204 N.W.2d 644, 646 (1973) (quoting Boynton Cab Co. v. Neubeck, 296 N.W. 636, 640 (1941)). Whether conduct is serious enough to justify losing both a job and reemployment benefits is primarily a fact-based inquiry. Ress, 448 N.W.2d at 524. The court generally considers one or more of these factors:

(1) whether an employee deliberately violated standards of behavior which the employer has a right to expect of its employee, (2) whether an employee's conduct adversely affected the business or other employee's morale, (3) whether an employee ignored past warnings.

 Id. Generally, if the employer's request is reasonable and does not unreasonably burden the employee, it is misconduct for the employee to refuse the request. Sandstrom v. Douglas Mach. Corp., 372 N.W.2d 89, 91 (Minn. App. 1985).

This court has found that the use of drugs while off-duty can be misconduct:

The employer's requirement that Hein abstain from illegal drug use while off-duty was reasonable in light of the public policy against such use. Hein committed misconduct "connected with" his employment because he violated the agreement which made his continued employment conditional upon remaining drug-free. Hein violated a standard to which his employer had the right to expect adherence. The actual drug use also constituted misconduct that interferes with employment because Hein operated heavy machinery that posed a danger to others if he were under the influence of drugs.

 Hein v. Gresen Div., 552 N.W.2d 41, 44 (Minn. App. 1996).

Here, relator admits that she used marijuana before testing positive on the first drug test, but denies that she used it again while on suspension. The commissioner's representative concluded, however:

The evidence shows that the claimant was in a safety sensitive position with the above-named employer and that her use of marijuana could have adversely affected the employer and prevented the claimant from properly performing her duties. * * * We note the reemployment insurance judge's finding of Fact Number 10 which states some information concerning marijuana remaining in the system for up to 60 days. We also note the Claimant's Exhibit Two which indicates that the concentrations of marijuana will be reduced due to elimination through the urine or by other steps. However, these documents do not indicate that the level of marijuana would actually rise some 20 days later if the claimant had not used marijuana between the first and second test. We further note the Employer's Exhibit Number Nine which is an opinion from a medical doctor concerning the results of the claimant's two tests. According to the doctor's opinion, "the medical probability is that Debra Miles . . . used marijuana between January 29, 1997 and February 18, 1997."

Because the findings of fact of the commissioner's representative are sustained by the evidence, we must determine whether, under these facts, relator's actions constitute misconduct.

Following Hein, and accepting the finding of the commissioner's representative that relator used drugs twice in violation of KRC's policy, we conclude the commissioner's representative did not err in determining relator committed misconduct under the law. The evidence supports the determination that by using drugs a second time, relator disregarded a prior warning and deliberately violated a standard that KRC reasonably expected her to follow in her safety sensitive position.

  Affirmed.