Hitachi ZAXIS 120-6 class Operator's Manual page 399

Precautions for Handling Batteries
 If electrolyte spills on your skin and/or clothes,
immediately flush the skin and/or clothes with water and
then wash further with soap.
If splashed in eyes, flush with water for approximately 15
minutes and seek immediate medical attention.
 Avoid using fire hazards such as matches lighters and
tobacco near the batteries. Do not allow sparks to fly.
 Check or service the battery only after stopping the
engine, turning the key OFF and removing the battery
caps.
 Contact with the battery just after operation may cause
personal injury.
Wait for the battery to cool.
 When the battery is recharged, inflammable hydrogen
gas is created. Remove the battery from the base
machine. Recharge the battery after removing the caps in
a well ventilated area.
 When disconnecting the battery terminals, first
disconnect the ground line [minus (-)] side terminal.
When connecting the battery terminals, connect the
ground line [minus (-)] side terminal last. If a piece of
metal, such as a tool comes in contact with the battery
plus (+) side terminal and the machine frame when both
terminals are connected, the electrical system may short-
circuit, possibly creating a dangerous situation.
 If a new battery is used along with an old battery, the
service life of the new battery may be shortened. Replace
two batteries at the same time.
 Loose terminal may allow sparks to fly. Securely tighten
the terminals.
MAINTENANCE
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