Wheatbelt police have warned truck drivers ignoring the rules on transporting dangerous chemicals and gasses could kill people in the event of a crash.
The message comes amid a crackdown on heavy freight carriers which has revealed trucks are carrying unsecured poisonous gases like chlorine, acid and explosives in the region.
Police allege on Friday they found 450 litres of highly toxic chlorine gas being carried in a load.
The driver was not carrying correct documentation or personal protective equipment and the vehicle was not displaying dangerous goods placards, Sgt Gerry Cassidy said.
The driver and company will be summonsed and police are also looking into whether the supplier may also face charges, Northam Police Acting Sgt Tony Osborne said.
Police say investigations over the past three months have revealed several incidents including one which found 440 kilos of fireworks improperly transported on the back of a truck.
Truck drivers, companies and suppliers have been warned they could face heavy fines for breaching the Dangerous Goods Safety Act (2004).