An inquiry into an explosion in which a number of police officers were badly burned has questioned the fire rating of new uniforms.

Victoria's police union raised the concerns an explosion in January, where three Melbourne-based officers were badly injured.

Police had been responding to a man threatening self-harm when the flat they were in exploded.

In subsequent inquiries, the Police union’s secretary Ron Iddles probed officials about the fire rating of officers' uniforms.

“We are concerned about the fire retardant features of the new police uniforms, particularly given that police officers can often find themselves in vulnerable situations involving fires,” Mr Iddles has told the ABC.

The union says the force must give officers the best materials possible to deal with their broad array of emergencies.

“These situations can exist in bushfires in country Victoria, house fires which are often discovered by our members who are the first on the scene dealing with a potentially dangerous situation,” Mr Iddles said.

“Also situations that involve explosions, as was the case in the Middle Park incident.”

The Victorian police service introduced a new set of uniforms for officers in 2012, which marked the first change to the official strip in thirty years.

Victoria Police has issued a statement saying new uniforms have been tested for fire resistance.

“Prior to being rolled out the new uniform was thoroughly tested, with specifications in line with regulations and the required Occupational Health and Safety standards,” the police command statement said.

“Victoria Police also consulted with the Police Association throughout the process.”

The Police Association, the officers’ union, now wants to know exactly what fire rating the uniform was given and from which specific material it is made.

The union says it would like to see the fire ratings of officers’ patrol pants, shirts, jerseys and the covering material of integrated operational equipment vests.