Weight limit manor farm road bridge, wembley?

Is there a weight limit for the bridge in question. Its Wembly, approaching from a4005 and straight thru to bilton road. Same route back.

No weight limits in my aa atlas and on google street view, but the approved route i get from the TM says its a 18t limit. Does anyone know?

Just passed it, no limits and it actually is the prefered route to perivale ind estate for DDs.