D.C. Mun. Regs. tit. 9, r. 9-444
Sales of natural or artificial gas, oil, electricity, solid fuel or steam are exempt from the payment of sales tax, except as provided in this section.
The sales tax applies to the receipts from the sale of natural or artificial gas, oil, electricity, solid fuel or steam when made to any purchaser for purposes other than resale or for use in manufacturing, assembling, processing or refining.
Sales for resale include only such sales when made to persons registered under § 146 of the Act and only then if that person gives the vendor a certificate of resale.
Receipts from the sale of natural or artificial gas, oil, electricity, solid fuel or steam consumed directly in manufacturing, assembling, processing, or refining (e.g., for operating machinery, lighting, and heating the factory or shop) are exempt from the tax.
The following are examples of manufacturing, assembling, processing and refining:
The use of natural or artificial gas, oil, electricity, solid fuel or steam incidental to but closely connected with production, such as lighting drafting rooms where products are designed, operating a first-aid room, and plant air conditioning, are considered as used in manufacturing, assembling, processing, or refining and are not subject to tax.
Natural or artificial gas, oil, electricity, solid fuel, or steam are subject to tax if consumed in administrative or commercial phases of the business activities listed in § 444.5, such as general offices, plant cafeterias (other than processing food), sales and display rooms, retail outlets, garages where trucks for off-premises sales of products are stored and serviced, and similar uses.
The tax shall not apply to the receipts from any of the types of sales exempted under D.C. Code § 47 -2005.
If electricity or gas shall be sold through a meter for a single use, or if oil, solid fuel, or steam shall be consumed in a single unit for a single use, the use determines the taxable status.
If electricity or gas is sold through a single meter for two (2) or more uses, or if oil, solid fuel, or steam is consumed in a single unit for two (2) or more uses, some of which would be subject to the tax and some of which would not (such as a manufacturing plant and a retail store supplied through one meter or heated by one unit), the larger portion of the use of the service supplied through that meter or consumed in that unit shall determine the taxability of the service. The larger portion of use shall be measured by the relative load for each use or the relative time of operation of each.
Except as otherwise provided in this section, each purchaser of natural or artificial gas, oil, electricity, solid fuel, or steam for any purpose claimed to be exempt from or not subject to the tax, in order to qualify for the exemption, must present evidence satisfactory to the Deputy Chief Financial Officer that the sale is exempt under the Act and this section, and must obtain from the Deputy Chief Financial Officer a specific exemption to be presented to the vendor.
After an exemption is presented to a vendor, that vendor shall be relieved from the further collection of reimbursement for the tax until the exemption is canceled by the purchaser, or is revoked by the Deputy Chief Financial Officer by notice given to both the purchaser and the vendor.
Vendors of natural or artificial gas, oil, electricity, solid fuel, or steam in the District are relieved from the collection of the reimbursement of the tax on sales to the United States through its Executive Departments and to the District of Columbia through its Purchasing Officers, where such purchaser of such natural or artificial gas, oil, electricity, solid fuel, or steam, claims to be an instrumentality of either the United States or the District of Columbia and, therefore, exempt from reimbursing the vendor for the tax. The vendor shall keep a record of sales to these government instrumentalities in the same manner and to the same extent as required in the case of semipublic institutions.
D.C. Mun. Regs. tit. 9, r. 9-444