The Welsh Ambulance Service is urging the public to stay safe.
The reminder comes ahead of Bonfire Night, which traditionally sees a spike in emergency calls for firework injuries, burns, and smoke inhalation.
Judith Bryce, assistant director of operations at the Welsh Ambulance Service, said: "Bonfire Night is a high-pressure evening for all emergency services across Wales so we're asking the public to take extra care, follow safety guidance, and help protect themselves, their families, and their communities.
"Many injuries, particularly burns, are preventable by following the Firework Code and taking simple precautions."
On Bonfire Night last year, the service received 1,142 emergency 999 calls and 1,763 non-emergency calls to NHS 111 Wales.
The public is urged to attend organised and professionally managed firework events, as they are safer than home displays.
The service also reminded the public to show consideration for emergency workers.
Ms Bryce said: "We know that calls to emergency services increase significantly around Bonfire Night, with reports of injuries, anti-social behaviour, and unsupervised fires.
"Our crews might have to withdraw from a scene if their safety is at risk, which helps no one, least of all the patient."