Hi mommy, sorry that I do not have answer whether there's a fridge at AST, hope there will be others who can help you.
Buy I do have a suggestion, you can consider a portable fridge.
It is a portable fridge which can keep contents cool for up to 12 hours.
It is light weight and waterproof.
Dimension:16cm (W) x 16.5cm (D) x 22.5cm (H)
-it can comfortably fit 4 Medela bottles 250ml.
http://www.fridge-to-go.com.sg/
If there is no proper nursing room available, hopefully there will be an available room for you to express milk and you may want to use a nursing cover.
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