You are a member if you have NTUC Union membership (not the Link rewards) and the company you work in is a member of HSEU (i.e. all public hospitals).

Interestingly, HSEU bothered to update their website to remove access to the Collective Agreements after the link was posted some time ago, but did not update anything else, like the list of HSEU branches and the newsletters still stuck in 2023.

HSEU has their priorities in making things opaque.