Lab. Code 2802 requires an employer to reimburse employees for expenses they incurred in working from home during the COVID-19 pandemic. It does not matter that the state’s emergency stay-at-home caused the employees to work from home rather than in an office. Lab. Code 2802 contains no causation requirement or excuse. Rather the section requires an employer to reimburse employees for all expenses they incur in performing their work whether or not the employer caused them to incur those expenses.