Q: California labor law regarding being oncall on weekend and off business hours as well as maintenance works after hours.

A: This is a bit of a law school exam question. . . really requires examination of the particular facts of your work, but here is a start at an answer.

You write that you are exempt. But just because the employer classifies you as exempt, does not mean you are exempt under the law. If you are not exempt, the employer would be required to pay you overtime by dividing your salary by your hours to obtain an hourly rate. To be exempt, the "primary duty" of your work would have to be exempt -- see below -- and you would have to make at least the salary listed below.

You would have to look at ALL of the work, including the work during regular hours -- in order to be exempt, your job has to meet the salary test AND the primary duty test below. So if more than half of your hours are in non-exempt work, you should be paid as an hourly employee, including overtime. The question is complicated by the on-call issue -- the factors looked at to determine whether on-call pay is required are:

excessive geographical restrictions on the employees movement;

whether the frequency of the calls was unduly restrictive;

whether a fixed time limit for response was unduly restrictive;

whether on-call employees could easily trade on-call responsibilities;

whether the use of a pager could ease restrictions;

whether the on-call waiting time is spent primarily for the benefit of the employer and its business;

whether the employee engaged in personal activities while on-call .

If you have to call in, that could also be a factor requiring payment.

So you would have to look at these factors to determine whether the on-call hours would be included in determining whether your "primary duties" -- see below -- are exempt or non-exempt.

The exemption question is always complicated -- the computer professional exemption is below (other exemptions could also apply. . . )

The compensation rates are adjusted annually for inflation according to the California Consumer Price Index (CPI) for Urban Wage Earners and Clerical Workers.[1] Effective January 1, 2020, employers must pay their California computer professional employees a salary of at least $96,968.33 annually ($8,080.71 monthly) or an hourly wage of $46.55 for every hour worked in order to remain exempt from paying such employees overtime compensation.[2] In addition to the increased salary requirement, California computer professionals must also still satisfy the duties test set forth under California Labor Code Section 515.5.

a computer professional must:

work as a computer systems analyst, computer programmer, software engineer, or other similarly-skilled worker in the computer field, AND

have, as his/her primary duty, either (1) the application of systems analysis techniques and procedures, including consulting with users, to determine hardware, software, or system functional specifications, (2) the design, development, documentation, analysis, creation, testing or modification of computer systems or programs, including prototypes, based on and related to user or system design specifications, (3) the design, documentation, testing, creation or modification of computer programs related to machine operating systems, or (4) a combination of the aforementioned duties, the performance of which requires the same level of skills.