General safety, Time/temperature relationships in scalds – Raypak WH & P L W User Manual
Page 8
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GENERAL SAFETY
To meet commercial hot water use needs, the high
limit safety control on this water heater is adjustable up
to 210°F. However, water temperatures over 125°F
can cause instant severe burns or death from scalds.
When supplying general purpose hot water, the rec-
ommended initial setting for the temperature control is
125°F.
Safety and energy conservation are factors to be con-
sidered when setting the water temperature on the
thermostat. The most energy-efficient operation will
result when the temperature setting is the lowest that
satisfies the needs of the application.
Water temperature over 125°F can cause instant
severe burns or death from scalds. Children, disabled
and elderly are at highest risk of being scalded.
•
Feel water before bathing or showering.
•
Temperature limiting valves are available.
Maximum water temperatures occur just after the
heater’s burner has shut off. To determine the water
temperature being delivered, turn on a hot water
faucet and place a thermometer in the hot water
stream and read the thermometer.
NOTE: When this water heater is supplying general
purpose hot water for use by individuals, a thermo-
statically controlled mixing valve for reducing point of
use water temperature is recommended to reduce
the risk of scald injury. Contact a licensed plumber or
the local plumbing authority for further information.
Water temperature over 125°F can
cause instant severe burns or death
from scalds.
Children, disabled, and elderly are
at highest risk of being scalded.
See instruction manual before set-
ting temperature at water heater.
Feel water before bathing or show-
ering.
Temperature limiting valves are
available, see manual.
Time/Temperature
Relationships in Scalds
The following chart details the relationship of water
temperature and time with regard to scald injury and
may be used as a guide in determining the safest
water temperature for your applications.
Water
Temp.
Time to Produce Serious
Burn
120°F
More than 5 minutes
125°F
1-1/2 to 2 minutes
130°F
About 30 seconds
135°F
About 10 seconds
140°F
Less than 5 seconds
145°F
Less than 3 seconds
150°F
About 1-1/2 seconds
155°F
About 1 second
Table courtesy of The Shriners Burn Institute
Table C: Time to Produce Serious Burn