[Bldg-sim] Health Care DHW Usage

[Fred Porter]

All;
I think 20-25 gallons/day per bed seems generous for a new cardiac facility (supposedly incorporating E-Star fixtures) without a laundry and with a kitchen. But the plumbing designer is sure this is low.  
 
Does anyone have a clear simple reference for average long term domestic hot water consumption (preferably measured/metered) in hospitals?
ASHRAE Applications lists 18 gpd/bed for "nursing homes," including their kitchens, but without "heavy laundry" and with the caveat that "data predate modern low-flow fixtures." 
A Massachusetts study of total domestic (so both hot and cold) water consumption in hospitals in the early 90's found 40 - 340 gpd/bed, which could even include lawn care.  
The 90.1-2004  Users Manual (pg G-32) includes some inputs for long-term DHW energy use for "Health/Institutional" (1100 Btuh/occupant x hourly schedule fractions) that imply about 15 gallons/day per "occupant" if that energy is for actually heating the water and does not include pipe losses. But the default occupancy density listed there is about 5x the bed density in this  proposed hospital, so using it would lead to 65 gpd/bed. 
The Green Guide for Health Care has about 60 separate occupancy categories with varying DHW rates, occupant densities and schedules; all the DHW rates are also in Btuh/person and vary from 0-1000 Btuh/person, typically 600 Btuh. These are supposedly taken from "90.1-2001 ECB Supplement Tables 7.1A & 7.1B" which are not in the body of 90.1-2001.
And I'm trying to separate energy use due to consumption and energy use due to pipe heat losses. I think I searched Transactions recently and did not find anything new regarding healthcare DHW. At this point I don't care about peak hours, or instant demand, just long term average.
 
Thanks if you can help;
 
Fred Porter
AEC
 
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