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Standard Interpretations - Table of Contents
• Standard Number: 1926.32(g); 1910.12(a); 1910.12(b); 1926.750(b)(1); 1926.750(b)(2); 1926.750(a); 1926.105; 1910.146

OSHA requirements are set by statute, standards and regulations. Our interpretation letters explain these requirements and how they apply to particular circumstances, but they cannot create additional employer obligations. This letter constitutes OSHA's interpretation of the requirements discussed. Note that our enforcement guidance may be affected by changes to OSHA rules. Also, from time to time we update our guidance in response to new information. To keep apprised of such developments, you can consult OSHA's website at

November 18, 2003

Mr. Raymond V. Knobbs
Minnotte Contracting Corporation
Minnotte Square
Pittsburgh, PA 15220

Re: Distinguishing construction from maintenance: whether classifying steel tanks and structural steel supports as plant equipment or plant structure alters categorizing their removal as maintenance or construction; how specific factors determine whether the removal and installation of steel tanks and structural steel supports will be considered in distinguishing construction from maintenance; what requirements apply to the removal and installation of steel tanks and supports.

Dear Mr. Knobbs:

This is in response to your letter dated May 5, 2003, to the Occupational Safety and Health Administration (OSHA). Your letter covers multiple questions pertaining to the classification of steel tanks and structural steel supports, what work OSHA considers maintenance vs. what is considered construction under 29 CFR Part 1926, and what OSHA regulations might apply to the owner of the property and to the controlling contractor during the work.

We have paraphrased your questions as follows:

Question (1): Do the following factors bear on whether work will be considered maintenance or construction: (a) the physical condition of the equipment/structure being worked on (whether it may be reused or if deterioration would require its complete removal); (b) replacement was performed to supplant deteriorated sections rather than to prevent the current parts from reaching a state of failure; (c) the physical characteristics (height, width, weight, material) of the equipment/structure; (d) the work is performed by an outside contractor rather than by a steel mill's own employees; (e) the work was performed during an annually scheduled work outage; and (f) whether steel tanks used in a mill plating line and the structural steel used to support the plating line, equipment and floor decking, are categorized as either plant equipment or plant structure?

In our
August 11, 1994 memorandum for Regional Administrators, our February 1, 1999 letter to Mr. Tindell, and our May 11, 1999 letter to Mr. Ellis, we discussed and gave examples of the difference between maintenance and construction work. These can be viewed on the Internet at (we have also enclosed a copy of each for your reference).

OSHA's regulations define construction work as "construction, alteration, and/or repair, including painting and decorating."
1 Section 1910.12(a) further provides that OSHA's construction industry standards apply "to every employment and place of employment of every employee engaged in construction work."2

Unlike construction work, there is no regulatory definition for "maintenance," nor a specified distinction between terms such as "maintenance," "repair," or "refurbishment." "Maintenance activities" have commonly been defined in dictionaries as making or keeping a structure, fixture or foundation (substrates) in proper condition in a routine, scheduled, or anticipated fashion. In OSHA's directive on the general industry confined space standard, the Agency stated that maintenance involves "keeping equipment working in its existing state, i.e., preventing its failure or decline"3 [emphasis added]. In applying this concept to the broad range of circumstances encountered in the construction industry, the factors discussed in the Tindell and Ellis letters and those discussed below must also be considered.

Construction work is not limited to new construction, but can include the repair of existing facilities or the replacement of structures and their components. For example, the replacement of one utility pole with a new, identical pole would be maintenance; however, if it were replaced with an improved pole or equipment, it would be considered construction.

In addition to the concept of one-for-one replacement versus improvement, the scale and complexity of the project are relevant. This takes into consideration concepts such as the amount of time and material required to complete the job. For example, if a steel beam in a building had deteriorated and was to be replaced by a new, but identical beam, the project would be considered a construction repair rather than maintenance because of the replacement project's scale and complexity. Also, if a bridge was to be stripped and re-painted, that would be considered construction work even if the repainting were done on a scheduled basis. Replacement of a section of limestone cladding on a building, though not necessarily a large project in terms of scale, would typically be considered construction because it is a complex task in view of the steps involved and tools and equipment needed to do the work.

As discussed in the Tindell letter, the physical size of an object that is being worked on can be a factor if, because of its size, the process of removal and replacement involves significantly altering the structure or equipment that the component is within. This is another example of how the project scale and complexity is relevant - if the process of removal and replacement is a large-scale project, then it is likely to be construction. It is not the classification of what you are working on as "equipment" or "structure" that is significant, but rather the project's scale and complexity.

Characteristics such as the material of the component are sometimes relevant in determining what specific standards apply, although by themselves such characteristics are unlikely to be an important factor in deciding whether an activity is considered maintenance or construction.

Whether the work is performed in-house or by an outside contractor is not a factor; it is not the personnel which will determine whether work will be considered maintenance or construction, but the work itself.

Work that is anticipated, routine and done on a regularly scheduled/periodic basis to help maintain the original condition of the component, will be suggestive of "maintenance," although this must be considered in light of the scale of the project. For example, whether a tank in your steel mill is repaired and reused versus replaced is not determinative. If the work consists of repair as opposed to replacement, a key factor is whether those repairs are extensive. If the work consists of removal and replacement of equipment, an important factor is whether the new equipment is of an improved type. For both the cases of repair and replacement, a key factor is the scale of the project, including the extent to which other equipment or structures must be moved, altered, etc. as discussed above.

Note that, though the work may itself occur during a scheduled "maintenance outage," this alone is not enough to qualify it as maintenance. For example, it is possible that the work may be construction, but scheduled during a maintenance outage to minimize lost productivity.

Question (2): Based on the characteristics described in Question (1), would the removal and replacement of steel tanks and the removal and replacement of the structural steel components be considered maintenance or construction under 29 CFR Part 1926?

Based on the information you have provided, the complete replacement of entire tanks and sections of structural support are large-scale projects, both with respect to time and material. In addition, you specifically state that the work being performed on both the steel tanks and the structural steel supports was undertaken because both had already reached a state of failure. The act of completely replacing the deteriorated tanks and support structures is an activity that goes beyond mere "refurbishment" and requires constructing replacements for structures (tanks) and plant components (structural supports). Also, unlike the scenario of replacing a single utility pole in a system of hundreds of poles, the tank replacements you describe form a significant portion of the system involved -- a system that will be significantly disrupted due to the work. Taking these factors together, the act of replacing the tanks and supports would be considered construction work under 29 CFR 1926.32(g) and 1910.12(b).

Question (3): Is the removal of the old structural steel components and the installation of new steel components (steel flooring/decking, structural steel beams) governed by Subpart R of 29 CFR Part 1926; what OSHA standards would pertain to the removal and replacement of the steel tanks?

Activities listed in §1926.750(b)(1) fall within the scope of Subpart R. Activities listed in §1926.750(b)(2) are covered by Subpart R "when they occur during and are a part of steel erection activities [listed in (b)(1)]."

Steel Decking
Section 1926.750(b)(1) contains a list of activities covered by Subpart R, including "installing metal decking * * *." Therefore, installing steel decking falls under Subpart R.

Subpart R is not limited to new construction; it also applies to steel erection activities in alteration and repair work. Under your scenario, the removal of the old decking is "repair." You are removing some but not all of the decking and replacing it with the same types of steel decking used in the original construction. Since §1926.750(a) states that steel erection activities done during repair are covered by Subpart R, the reverse of the decking installation process - removal - is also covered under §1926.750(b)(1).

Structural steel beams
Under §1926.750(b)(1) "steel erection activities include * * * placing, connecting * * * and rigging structural steel." The definition of "structural steel" includes steel beams. Therefore Subpart R applies to the installation of structural steel beams. Subpart R also applies to the removal of the steel beams for the same reasons as above. The removal of these beams is steel erection work done during "repair."

Steel Tanks
Section 1926.750(a) states:
* * * This subpart does not cover electrical transmission towers, communication and broadcast towers, or tanks.
Therefore, the removal and replacement of the tanks is not covered by Subpart R. Fall protection for that work is governed by §1926.105.

Components/structures supporting steel tanks
In Question 5 of the
Steel Erection Directive (which can be viewed at, we implicitly indicated that the exclusion of tank construction from Subpart R does not also exclude work on the steel structure on which the tank rests:
Question 5: When a tank is to be supported by a structure that falls under the scope of Subpart R, does construction of the tank also fall within the scope of Subpart R?
Answer: No. 1926.750(a) excludes tank construction from the scope of Subpart R. It is excluded because it is considered to be a specialized industry based upon its unique use of cylindrical construction techniques. The construction of the tank itself would not be steel erection even though the structure supporting the tank is covered by subpart R. [Emphasis added.]
Based on the information you submitted, work on the structural steel components that support the tank would be covered under Subpart R.

In sum, given your scenario the removal of the old structural steel components and the installation of the new steel components (steel decking, structural steel beams) are governed by Subpart R of 29 CFR Part 1926 while the removal and reinstallation of the steel tanks are not.

If you need additional information, please contact us by fax (202-693-1689) at: U.S. Department of Labor, OSHA, Office of Construction Standards and Guidance. You can also contact us by mail at U.S. Department of Labor, OSHA, Office of Construction Standards and Guidance, Room N3468, 200 Constitution Avenue, N.W., Washington, D.C. 20210, although there will be a delay in our receiving correspondence by mail.


Russell B. Swanson, Director
Directorate of Construction

>1 29 CFR 1926.32(g) and 1910.12(b).
[ back to text ]

2 Also relevant to the distinction between construction and maintenance are the Davis-Bacon Act regulations. In essence, 29 CFR 5.2(i) defines construction work as "generally includ[ing] construction activity as distinguished from manufacturing, furnishing of materials, or servicing and maintenance work * * *." [ back to text ]

3 CPL 02-00-100 [formerly CPL 2.100] - Application of the Permit-Required Confined Spaces (PRCS) Standards, 29 CFR 1910.146. [ back to text ]

4 The factors mentioned above are not intended to constitute an exhaustive list of the considerations that are involved in distinguishing construction from maintenance. [ back to text ]

5 We note that the replacement and installation of the steel tanks and structural supports would have occurred regardless of whether there was a scheduled "work outage" for maintenance because, as you said, they were already at a point of failure. [ back to text ]

Standard Interpretations - Table of Contents

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