🔍 Key Concepts

• Electrolysis and gassing during battery charging (hydrogen and oxygen production) • Difference between poisonous vs explosive gases • Purpose of ventilation in enclosed machinery or battery spaces

💭 Think About

• When lead‑acid batteries are charged, what gas is commonly produced at the end of charge, and what is its main hazard? • Is the primary concern in a battery room that people will be poisoned, or that a certain concentration of gas could create another type of danger? • Think about why SOLAS and USCG rules require ventilation in spaces where flammable vapors may be present.

✅ Before You Answer

• Identify what gas is released from lead‑acid batteries during overcharging (hint: hydrogen). • Recall whether hydrogen is more known for being toxic or flammable/explosive. • Consider which choice directly addresses the safety risk that ventilation is intended to control in an enclosed battery room.