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  <xs:element id="omcl_IncreaseDecreaseInOperatingLeaseLiabilities" abstract="false" name="IncreaseDecreaseInOperatingLeaseLiabilities" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="omcl_PaymentsforSoftwareForExternalUse" abstract="false" name="PaymentsforSoftwareForExternalUse" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="omcl_LeaseReceivableMember" abstract="true" name="LeaseReceivableMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="omcl_A2009PlanMember" abstract="true" name="A2009PlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="omcl_SaleofStockAvailableforIssuance" abstract="false" name="SaleofStockAvailableforIssuance" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
