Section 312. Exclusiveness of remedy

Compensation  as provided in this
  article shall be the exclusive remedy of a civil  defense  volunteer  or
  his  or  her  spouse, dependents, executor or administrator, for injury,
  disease or death arising  in  the  course  of  civil  defense  volunteer
  service,  as against the state or any political subdivision of the state
  or civil defense agency or any  person  or  other  agency  acting  under
  governmental authoritiy in furtherance of civil defense activities, with
  or  without  negligence,  except  only  as  otherwise provided by law. A
  member of a civil defense agency of the federal government or of another
  state or of the Dominion of  Canada  or  a  province  thereof,  who  may
  perform  services  within  this  state, whether pursuant to a mutual aid
  compact or otherwise, shall not be entitled to  compensation  under  the
  provisions of this article.