Current textIn force on Sept. 30, 1998Source: annual CFR editions 1996–2016

§ 325.77 Computation of open site requirements—nonstandard sites.

Current wording, first on file in the 1996 annual edition.

govinfo, 1996 edition ↗

Before Jan. 1, 2017 the record is one snapshot per annual CFR edition, revised as of October 1. This is the 1996 edition's wording. An amendment that took effect between Oct. 1, 1997 and Sept. 30, 1998 would not appear until the next edition, so check the citations below and the Federal Register for exact effective dates. govinfo does not publish the 1997 edition of Parts 300–399 in machine-readable form, so the 1996 text is shown for that year.

49 CFR § 325.77 — Computation of open site requirements—nonstandard sites.. Text in force on September 30, 1998. This wording effective October 1, 1996 to present. Source: govinfo, 1996 edition, https://www.govinfo.gov/app/details/CFR-1996-title49-vol4/CFR-1996-title49-vol4-sec325-77. Retrieved from FMCSR.com, https://fmcsr.com/reg/325.77?asof=1998-09-30, on October 26, 2026. Unofficial compilation; verify against the official source.

(a) If the distance between the microphone location point and the microphone target point is other than 50 feet (15.2 m), the test site must be an open site within a radius from both points which is equal to the distance between the microphone location point and the microphone target point.

(b) Plan view diagrams of nonstandard test sites are shown in Figures 3 and 4. Figure 3 illustrates a test site which is larger than a standard test site and is based upon a 60-foot (18.3 m) distance between the microphone location point and the microphone target point. (See § 325.79(b)(1) for an example of the application of the correction factor to a sound level reading obtained at such a site.) Figure 4 illustrates a test site which is smaller than a standard test site and is based upon a 35-foot (10.7 m) distance between the microphone location point and the microphone target point. (See § 325.79(b)(2) for an example of the application of the correction factor to a sound level reading obtained at such a site.)

Amendment history

1 distinct wording on file since Oct. 1, 1996

Oct. 1, 1996 → presentannual editions 1996–2016viewing

A new entry appears whenever the regulatory words change between government snapshots. Day-precise from the eCFR (2017 onward); before that, one snapshot per annual CFR edition (revised as of October 1). Bracketed citations are the Federal Register history printed with the section.