Modifiers matching radiator:

• acoustic,
• active,
• passive,
• complex,
• big,
• efficient,
• dirty,

Simple categories matching dirty:

• environment,
• fuel,
• surface,
• paving,
• air,
• area,
• object,
• matter,
• item,
• work,
• material,
• place,
• liquid,
• machine,
• implement,
• textile,
• activity,
• substance,
• dish,
• gear,
• linen,
• fluid,
• artist,
• radiator,
• tank,
• space,
• condition,
• job,
• room,
• footwear,
• os,
• process,
• thing,
• particle,
• location,