Is there a way to add a “required” type clause to ensure a is changed before submit?

The HTML form has :

<form class="form-horizontal" method = "POST" action ="sw_save.php">

and the submit is:

<button type="submit"  name= "submit" id= "submit" class="btn btn-primary"><span class = "fa fa-save"></span> Save</button>

Within the form are a few inputs with the required attribute, but there is also a select with an initial:

<option value ="0">Select Operative</option> 

The remainder of the options are filled from a table (using PHP) with the value being the operative id and the display being the operative name.

Currently the check is made in the initial stage of the called PHP page and if value is 0 returns to the form page.

Is it possible to simulate a “required” type attrribute (whether by JSchange or other means) to ensure that the option value is not 0 before alllowing submit, so can indicate change is required e.g. only enable save button if select value is >0 ?