Addendum L, DLTO Test Exception, revises the criteria of Standard 301-2014, Table 4.2.2(1) note (m) exception for testing duct leakage to outdoors created by Addendum D-2017. The exception applies where the criteria are met for ducts located within conditioned space. Addendum T, Distribution System Efficiency (DSE), revises Standard ANSI/RESNET/ICC 301 to eliminate the prescriptive requirement for software not employing hourly simulations to comply with ASHRAE Standard 152. RESNET software accreditation requirements of Publication 002 separately establish performance criteria that ensure the accuracy of rating software. These addenda take effect and supersede previous requirements on January 1, 2019. Note however that the MINHERS® Chapter 5 provides for now: 503.2 Where an amendment alters a Confirmed, Threshold or Sampled rating that is established between a rater and client prior to the date of public notice and publication of the amendment on the RESNET website, a transition period shall be allowed. Dwelling Units with a building permit date within 6 months of the Effective Date of the amendment shall be allowed to use the requirements that preceded the amendment. Visit /wp-content/uploads/archive/resblog/2018/04/RESNET-Pending-Standard-Amendments-3-28-18-Completed.pdf for the status of pending standard amendments.