NodeJS is reading the same file blocking?

Question

We have a backend expressjs server that will read off of the disk for many files whenever a front-end client connects.

At the OS level, are these reads blocking?

I.E., if two people connect at the same time, will whoever gets scheduled second have to wait to read the file until the first person who is currently reading it finishes?

We are just using fs.readFile to read files.

EDIT: I'm implementing caching anyway (it's a legacy codebase, don't hate me), I'm just curious if these reads are blocking and this might improve response time from not having to wait until the file is free to read.