Nurses in public hospitals in Nakuru downed their tools on Wednesday over the county's failure to pay their July and August salaries.
They demonstrated outside Nakuru Level Five Hospital, led by Bernard Njoroge, who is Nakuru chairman of the Kenya National Union of Nurses (Knun).
The health workers said Nakuru dishonoured its promise to pay them on time following a series of meetings.
"We have decided to stay away from our working stations until the county honours its promise. Nurses have suffered for two months now," said Mr Njoroge.
They also complained about the lack of promotions for 400 of them since January.
Those due for promotions forwarded their letters to the county government.
According to Mr Njoroge, 200 nurses promoted during the 2016-17 financial year are yet to receive their arrears.
"The county has failed us so we are asking it to consider handing the docket back to the national government," the chair said.
In a notice dated August 3, Nakuru promised to pay the salaries by August 28.
The letter was signed by Festus Ng'eno, the County Executive Committee (CEC) Member for Health.