10 CFR § 429.30 - Water closets.

§ 429.30 Water closets.

(a) Sampling plan for selection of units for testing.

(1) The requirements of § 429.11 are applicable to water closets; and

(2) For each basic model of water closet, a sample of sufficient size shall be randomly selected and tested to ensure that any represented value of water consumption of a basic model for which consumers favor lower values shall be greater than or equal to the higher of:

(i) The mean of the sample, where:

x = 1 n i = 1 n x i and, x is the sample mean; n is the number of samples; and x i is the i th sample;

Or,

(ii) The upper 90 percent confidence limit (UCL) of the true mean divided by 1.1, where:

U C L = x + t . 90 ( s n ) And x is the sample mean; s is the sample standard deviation; n is the number of samples; and t 0.90 is the t statistic for a 90% one-tailed confidence interval with n-1 degrees of freedom (from Appendix A).

(b) Certification reports.

(1) The requirements of § 429.12 are applicable to water closets; and

(2) Pursuant to § 429.12(b)(13), a certification report shall include the following public product-specific information: The maximum water use in gallons per flush (gpf), rounded to the nearest 0.01 gallon. For dual-flush water closets, the maximum water use to be reported is the flush volume observed when tested in the full-flush mode.

[76 FR 12451, Mar. 7, 2011; 76 FR 24771, May 2, 2011, as amended at 78 FR 62986, Oct. 23, 2013]