http://www.eptis.bam.de/
The EPTIS database <http://www.eptis.bam.de/ept_s1_frame.htm> lists
hundreds of PT schemes (PTS) operated in Europe and the U.S.. It aims at
helping you to find a suitable PTS in this quite intransparent market.
The focus is on the field of testing; metrological and clinical PTS are
not included systematically. EPTIS is a non-commercial, joint
publication of 19 international organisations
<http://www.eptis.bam.de/contact.htm> in Europe and the Americas, and
open <http://www.eptis.bam.de/join.htm> for further international
participation.