Strength testing concrete and mortar before steel erection

August 23, 2004

Dennis Vance

Dennis Vance Safety, LLC

[Recipient address omitted]

Re: Employer's obligations in the steel erection standard (29 CFR Part 1926 Subpart R) under §1926.752(a)(1) with respect to testing concrete and/or mortar in a masonry wall.

Dear Mr. Vance:

This is in response to your April 14, 2004, e-mail to the Occupational Safety and Health Administration (OSHA) regarding §1926.752(a)(1)'s requirement for compressive-strength testing of concrete and mortar in a masonry wall during steel erection.

We have paraphrased your questions as follows:

Question (1): In a December 27, 2002 letter to Mr. Sean Purcell OSHA stated, "Since there currently is no ASTM standard test method to test the compressive strength of field-cured mortar, OSHA will not enforce the requirements of §1926.752(a)(1) until such time as we are able to define an appropriate substitute or until an appropriate ASTM test method is developed." Did OSHA suspend the enforcement of the entire §1926.752(a)(1) standard or only the section of the standard requiring compressive strength testing of mortar?

Answer:

Title 29 CFR 1926.752(a) states:

(a) Approval to begin steel erection. Before authorizing the commencement of steel erection, the controlling contractor shall ensure that the steel erector is provided with the following written notifications:

(1) The concrete in the footings, piers and walls and the mortar in the masonry piers and walls has attained, on the basis of an appropriate ASTM standard test method of field-cured samples, either 75 percent of the intended minimum compressive design strength or sufficient strength to support the loads imposed during steel erection.

OSHA suspended enforcement only of the requirement for compressive-strength testing of field-cured mortar. The rationale for the suspension was the absence of an ASTM test method for testing the compressive strength of field-cured mortar. Conversely, there is an ASTM standard test method for testing the compressive strength of the concrete in the footings, piers, and walls. Therefore, pursuant to §1926.752(a)(1), employers must continue to test the concrete in the footings, piers, and walls on the basis of an appropriate ASTM standard test method of field-cured samples.

Question (2): If concrete is used to grout hollow concrete blocks when building a masonry wall, would it be considered "concrete in the footings, piers, and walls" under §1926.752(a)(1) and, therefore, be required to be tested using an appropriate ASTM test method?

Answer:

Yes. Concrete used to grout hollow concrete blocks when building a masonry wall is considered "concrete in the footings, piers, and walls" under §1926.752(a)(1) and therefore, must be tested on the basis of an appropriate ASTM standard test method.1

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

Sincerely,

Russell B. Swanson, Director

Directorate of Construction

1 However, note that, due to the absence of an ASTM standard test method for mortar, the concrete ASTM test may not wholly verify whether a masonry wall is sufficiently strong to support the loads imposed during steel erection. [ back to text ]