TP26-14 Plumbing Design: A Hidden Legionella Defense

Legionella in building water systems can result from multiple, often complex 
variables. Identifying the true cause(s) of Legionella can be critical for risk 
minimization and legal defense. Proper plumbing design precedes and may preempt 
the success of construction, management, maintenance, and treatment. Nonetheless, 
the plumbing design aspect of the building water system has been historically 
misunderstood by plumbing design professionals, undervalued by engineering 
firms, and overlooked by cause and origin experts. The lack of a proper plumbing 
design can cause a litany of issues resulting in recurring positivity. Some of the 
usual suspects include improperly designed and poorly commissioned water 
systems and failure to know and apply industry codes, standards, guidelines, and 
manuals. This paper will highlight how a better understanding of plumbing design 
can assist in both the prevention of Legionella cases and the development of merits
based legal defenses. This paper will also orient the reader with technical concepts 
and industry publications along with case studies so they may potentially identify 
often-overlooked design related root causes of Legionella positivity.