Honda 1993 Accord Coupe Owner's Manual page 37

Coolant Temperature Gauge
Do not remove the radiator cap when the engine is hot. The
coolant is under pressure and may blow out and scald you.
This gauge shows the temperature of the engine coolant. During
normal operation, the needle should stay in the middle of the white
range. Under severe driving conditions, such as hot weather or
driving uphill for a long period, the needle may rise toward the upper
section of the white range.
if the needle reaches the red line at " H " (Hot), pull safely off the
road and stop the engine.
Wait until the engine is cool and check the coolant level in the
reserve tank on the passenger side of the radiator under the hood.
(See pages 122 — 123.)