Dangerous goods are substances and objects that could cause danger during a flight. Special care is required here. The Federal Aviation Authority (Luftfahrtbundesamt) provides detailed information on this topic.
Fireworks of any kind (including sparklers or table fireworks) may not be taken or carried in either hand or checked baggage.
Other examples of dangerous goods: Explosives, ammunition, gases, flammable solids, flammable liquids such as camping gas cartridges, knockout sprays, smoking paraphernalia (e.g. e-cigarettes, lighter refill cartridges), petrol and storm lighters, "anywhere lighters" with a blue flame. Special rules also apply to diving equipment.
Rules for lighters: Common lighters may be carried close to the body, for example in the trouser pocket. Quantity is limited to one piece per person.