What is a non-sparking metal?

• A. Steel
• B. Aluminum
• C. Brass
• D. Copper

Answer: (B)

Non-sparking metals are chosen for work around flammable vapors or dusts because they are unlikely to throw off ignition-causing sparks when struck or ground. Aluminum fits this description well: it’s non-ferrous and relatively soft, so when it’s tapped or used as a tool it tends to deform rather than produce bright, hot sparks like steel does. That reduced spark output lowers the ignition risk in hazardous environments. In contrast, steel contains iron and is prone to producing noticeable sparks when struck; copper and brass are also copper alloys with low sparking tendencies, but the common safety distinction in this context is that aluminum is treated as a non-sparking option.