Opinion by
Judge Wilkinson,These appeals arise from an adjudication of the Court of Common Pleas of Allegheny County which sustained in part and reversed in part real estate tax assessments by the Board of Property Assessment, Appeals and Review of Allegheny County and the Board of Revision of Taxes and Appeals of the City of Clairton (hereinafter referred to collectively as the Boards). In 1968, appellees included in their real estate tax assessments of appellant’s Clairton facilities a regenerator building at $185,000 and three ammonia tanks at $125,000 each. Following dismissals of the appeals by the Boards, appellant filed an appeal from each dismissal to the Court of Common Pleas of Allegheny County. Because of the similarity of the appeals they were consolidated for hearing both here and below. The lower court sustained the appeals as to the regenerator building, but refused the appeals as to the three ammonia tanks. The Boards did not appeal the decision as to the regenerator building.
The question presented to this Court is whether or not the ammonia tanks in question are to be excluded for purposes of the real estate assessment. The pertinent statutory authority is Section 201 of the General County Assessment Law, Act of May 22, 1933, P.L. 853, as amended, 72 P.S. §5020-201, which provides in part:
The following subjects and property shall, as hereinafter provided, be valued and assessed, and subject to taxation for all county, city, borough, town, township, school and poor purposes at the annual rate:
*425(a) All real estate, to wit: House, house trailers and mobilehomes buildings permanently attached to land or connected with water, gas, electric or sewage facilities, buildings, lands, lots of ground and ground rents, trailer parks and parking lots, mills and manufactories of all kinds, furnaces, forges, bloomeries, distilleries, sugar houses, malt houses, breweries, tan yards, fisheries, and ferries, wharves, and all other real estate not exempt by law from taxation. Machinery, tools, appliances and other equipment contained in any mill, mine, manufactory or industrial establishment shall not be considered or included as a part of the real estate in determining the value of such mill, mine, manufactory or industrial establishment. ...
This section has become known as the ‘ ‘ Machinery Exclusion.” The issue before us is whether or not the three ammonia tanks are within the “Machinery Exclusion, ’ ’ and thus excluded from the assessment.
The leading case authority in this area is Jones and Laughlin Tax Assessment Case, 405 Pa. 421, 175 A.2d 856 (1961).1 In that case the Supreme Court, after a careful review of the prior law, set out the criteria to be used in determining whether or not property is within the “Machinery Exclusion”:
Therefore, it is our considered conclusion, under the statute involved, improvements, whether fast or loose, which are used directly in manufacturing the products that the establishment is intended to produce and are necessary and integral parts of the manufacturing process and are used solely for effectuating that purpose, are excluded from real estate assessment and taxation. On the other hand, improvements which benefit the land *426generally and which may serve various areas of the land, are not in this category. Neither are structures, which are not necessary and integral parts of the manufacturing process and which are separate and apart therefrom, within the exclusion. A structure used for storage, for example, is part of the realty and subject to real estate taxation. (Emphasis in original.)
Jones and Laughlin, supra, 405 Pa. at 431, 175 A.2d at 861.
It is important to note the emphasis placed on the words “directly” and “solely” by the Supreme Court.
In United States Steel Corp. v. Board of Assessment and Revision of Taxes, 422 Pa. 463, 223 A.2d 92 (1966), the Supreme Court applied the criteria of Jones and Laughlin, supra. While not going through the entire Jones and Laughlin facility piece by piece the Court did discuss several pieces of property individually, one such being the ‘ ‘ ore yards. ’ ’ The problem concerning the “ore yards” was that they served as a temporary storage area. The Court stated that:
While these ore yards may be used for temporary storage [footnote omitted] such use is minimal and purely incidental to their use as necessary and integral parts of the process of manufacturing steel.
United States Steel Corp., supra, 422 Pa. at 470, 223 A.2d at 96.
Thus, the Court held that the “ore yards” were to be excluded from the tax assessment.
In the instant case the storage capabilities of the ammonia tanks are neither incidental nor temporary. On the contrary, the record reveals that the tanks in question are used primarily for the storage of ammonia.2 The purification and quality control proc*427esses are incidental to the primary function of these structures as storage tanks. As such, under the criteria laid down by the Court in Jones and Laughlin, supra, and United States Steel Corp., supra, the three tanks should be included in the tax assessment and deemed not to be within the “Machinery Exclusion.” The tanks are not used “directly” in the manufacture of ammonia, nor are they “necessary and integral parts of the manufacturing process. ’ ’
In the instant case, Judge Hester of the Allegheny County Court of Common Pleas, in a very well considered opinion, determined:
It is our considered opinion that the tanks in question are used for both the processing as well as the storage of the ammonia.
There can be no question that the three tanks in question are used in the ‘Keystone Project’ for the production of ammonia as one of the By-products realized from the conversion of coal into coke. However, there can also be no question that said tanks are further used for the storage of said ammonia following its production. Ergo, the tanks are used directly in manufacturing process, but they are not used solely for effectuating that purpose. They therefore fail to meet the test laid down in the U.S. Steel Corporation vs. Board of Assessment and Revision of Taxes (supra) and cannot be considered as excluded from the assessment.
*428If we were to disagree with Judge Hester, it would he that the tanks here involved are used very incidentally, if at all, in the production and manufacture of ammonia. Their primary, if not exclusive use being storage. The chemical changes effected during the stay in the tanks is for purposes of holding the ammonia and to maintain its purity during storage.
Appellant relies heavily on Gulf Oil Corp. v. Philadelphia, 357 Pa. 101, 53 A.2d 250 (1947). This reliance is misplaced. The issue in Gulf Oil, supra, was not whether the tanks were an integral part of the refining of oil, but rather whether the chemical and mechanical processes that took place in these tanks could cause the tanks to be classified as machinery. Likewise, appellant’s reliance on Gordon Lubricating Co. v. Allegheny County Board of Property Assessment, Appeals and Review, 204 Pa. Superior Ct. 441, 205 A.2d 704, aff’d per curiam, 418 Pa. 625, 211 A.2d 284 (1964), is equally misplaced. The Superior Court made it very clear that the tanks involved therein were not for storage, but in fact, something was constantly happening in the tanks so as to make them an integral part of the manufacturing operations. This is simply not the case with the three ammonia tanks involved herein. Therefore, the Gulf Oil, supra, and Gordon Lubricating, supra, cases are distinguishable.
Accordingly, we will enter the following
Order
Now, December 9, 1976, the order of the Court of Common Pleas of Allegheny County, dated July 9, 1975 is affirmed and the appeals dismissed.
The statute construed in Jones and Laughlin is substantially similar to tbe one in the case before us.
On direct examination, appellant’s expert was asked:
“Q. Mr. Haddad, I show you Exhibit No. 2 and ask if you can identify it?
*427“A. This is a photograph of the three tanks that make up a part of the ammonia refrigeration storage system that we havé.”
On cross-examination, the same expert testified:
“Q. The real function of the tank is that it holds the ammonia and then the ammonia is extracted and then put through these various lab tests that you described?
“A. That is correct.”