What is the syntax used in the ESRI ArcGIS Portal Feature Service Where Clause:

I've connected to my ArcGIS Portal and can read a feature service. I want to add several where clauses to narrow down this read each time. Adding "objectid">0 returns records, adding "workerid"=88 returns records, but I can't figure out the syntax to apply both in the same where clause. When using the REST API directly its just where=ObjectID>0&workerid=88 and this returns multiple records. But in FME it returns 0

Any ideas how i can combine multiple conditions in my where clause?