Bradford White RG1D Installation & Operation Instructions page 15

Installation (Water Connections) continued-
Hydrogen gas can be produced in an operating water heater that has not
had water drawn from the tank for a long period of time (generally two
weeks or more). Hydrogen gas is extremely flammable. To prevent the
possibility of injury under these conditions, we recommend the hot water
faucet to be open for several minutes at the kitchen sink before you use
any electrical appliance, which is connected to the hot water system. If
hydrogen is present, there will be an unusual sound, such as air escaping
through the pipes as hot water begins to flow. Do not smoke or have
open flame near the faucet at the time it is open.
This water heater can deliver scalding temperature water at any faucet in the
system. Be careful whenever using hot water to avoid scalding injury. Certain
appliances, such as dishwashers and automatic clothes washers may require
increased temperature water. By setting the thermostat on this water heater
to obtain increased water temperatures, the potential for scald injury
increases. To protect against injury, you should install an ASSE approved
mixing valve in the water system. This valve will reduce point of discharge
temperature by mixing cold and hot water in branch supply lines. Such valves
are available from the manufacturer of this water heater or a local plumbing
supplier. Please consult with a plumbing professional.
APPROXIMATE TIME/TEMPERATURE RELATIONSHIPS IN SCALDS
120°F (49°C)
125°F (52°C)
130°F (54°C)
135°F (57°C)
140°F (60°C)
145°F (63°C)
150°F (66°C)
155°F (68°C)
WARNING
More than 5 minutes
About 30 seconds
About 10 seconds
Less than 5 seconds
Less than 3 seconds
About 1½ seconds
15
1½ to 2 minutes
About 1 second