Scald Safety
Maximum Water Temperature Standards
§Recommended maximum residential standard
§      120°F (48°C) 
§         (U.S. Consumer Product Safety Commission)
§
§Nursing homes and child care facilities
§       110°F (43°C)
§       (Recommended and by some state or local
§           regulations)
§                                                                                          
The U.S. Consumer Product Safety Commission recommends 120°F (48°C) as a maximum setting for residential water heaters. As we noted, it would take an estimated 5 minutes of exposure before water of this temperature would cause a serious burn in a healthy adult.
Regulations for nursing homes and child care facilities are established in some state or local communities and they typically cite 110°F (43°C) as the maximum allowable temperature for patient accommodations That’s because a setting that allows water temperature to reach 120°F may be too high for young children or older adults. A temperature of no more than 100°F is considered safest for bathing a baby.
(Bridge)   Unlike the thermostats that control house heating systems, water heater thermostats don’t usually have temperature settings. How can I measure the actual water temperature?