Article 5

     1. National  laws  or regulations shall make appropriate persons,
whether employers,  owners,  masters or other persons, as the case may
be,  responsible  for  compliance  with  the  measures  referred to in
Article 4, paragraph 1, of this Convention.
     2. Whenever   two   or   more   employers   undertake  activities
simultaneously  at  one  workplace,  they  shall  have  the  duty   to
collaborate  in order to comply with the prescribed measures,  without
prejudice to the responsibility of each employer for  the  health  and
safety of his employees.  In appropriate circumstances,  the competent
authority shall prescribe general procedures for this collaboration.