Greetings, The National Oceanic and Atmospheric Administration (NOAA) is pleased to announce the availability of a revised version of the "Draft NOAA Guidance for Assessing the Effects of Anthropogenic Sound on Marine Mammal Hearing: Acoustic Threshold Levels for Onset of Permanent and Temporary Threshold Shifts" for *a second 45-day public comment period that opens July 31, 2015*. The changes to the updated version of this document are based on recent science and comments from the initial public comment period (December 2013-March 2014). NOAA has developed draft guidance for assessing the effects of anthropogenic sound on marine mammal species under NOAA’s jurisdiction. The guidance, based on the best available science, provides updated received levels, or acoustic threshold levels, above which individual marine mammals are predicted to experience changes in their hearing sensitivity (either temporary or permanent) for all underwater anthropogenic sound sources. This guidance is intended to be used by NOAA analysts and managers, other federal agencies, and other relevant user groups and stakeholders who are seeking to determine if their activities are expected to result in particular types of impacts to marine mammals via acoustic exposure. Electronic copies of the document can be found at: http://www.nmfs.noaa.gov/pr/acoustics/guidelines.htm and the Federal eRulemaking Portal http://www.regulations.gov. Comments may also be submitted via the Federal eRulemaking Portal beginning July 31st ( http://www.regulations.gov, search for NOAA-NMFS-2013-0177). Thank you for your interest in the guidance document. For more information, please contact Amy Scholik-Schlomer (amy.scholik@noaa.gov or 301 427-8449). Jonathan Shannon *Outreach Specialist* NOAA Fisheries Office of Protected Resources U.S. Department of Commerce Office: 301-427-8431 jonathan.shannon@noaa.gov *Webhttp://www.fisheries.noaa.gov/pr/ <http://www.fisheries.noaa.gov/pr/>Facebookwww.facebook.com/noaafisheries <http://www.facebook.com/noaafisheries>Twitterwww.twitter.com/noaafisherie <http://www.twitter.com/noaafisheries>sYouTubewww.youtube.com/usnoaafisheriesgov <http://www.youtube.com/usnoaafisheriesgov> The views expressed in this message are my own and do not necessarily reflect any position of NOAA, the Department of Commerce, or the government of the United States.*