Rail Transit Platform Door & Noise Control Sealing

A platform screen door closes against a train that never stops in exactly the same place, and a train door runs against its frame thousands of times a day. A rubber lip has to be compressed every time, wears, and fights the door when the gap is tight. A brush seal bends instead. It closes a gap that varies, lets the door slide through it and keeps working as it wears.

Its job here is not cleaning. It keeps out dust and drafts, cuts noise through the gap, and keeps brake and rail dust and track spray out of equipment compartments and cable entries under the car.

Rail adds one requirement most sealing jobs do not have: fire performance. Every material in a passenger area or on rolling stock has to meet the project’s fire, smoke and toxicity standard.

Sizes from the strip seal brushes we make:

Size the trim from the gap, not the door. Measure the gap at its widest and narrowest over the door’s travel, then set the trim so the brush is still compressed 10–25% at the widest point. At the narrowest it bends further, which a brush tolerates and a rubber lip does not.

For noise, density matters more than height: a tightly packed fill breaks the sound path. For cable entries, two strips facing each other let the bundle pass between them and close round it.

Send the fire requirement with the enquiry, the EN 45545-2 hazard level or the NFPA 130 clause, and the fill, holder and any end caps are chosen against it. The test evidence the project needs is agreed before sampling.

• Fit the holder to slotted holes, so the trim can be set to the measured gap on site.
• Check the compression over the full door travel, at both ends of the gap.
• Inspect at the rail operator’s maintenance interval; a seal with a permanent gap in the fill needs resetting or replacing.
• Replace strips as complete lengths, so the fill height stays even along the door.

• The gap: widest and narrowest over the door’s travel, and the length.
• Door, platform screen door, trackside or compartment, and indoor or outdoor.
• Holder profile and fixing, or a drawing of the mounting.
• The project’s fire, smoke and toxicity requirement.
• Quantity per length and profile; for medium and large brushes the minimum is 100 pieces.

A brush seal blocks dust, drafts and noise; it does not hold water or air pressure. Where a door must be watertight or pressure-sealed, use a rubber or inflatable seal and add the brush in front of it as a dust barrier.

• Setting the trim at the narrowest gap, so the seal stands open when the gap widens.
• Over-compressing the fill, which bends it permanently and slows the door.
• Choosing the fill before the fire requirement is known.
• Fixing the holder with round holes, so it cannot be adjusted on site.