Silicon Valley janitors went on strike today over low wages and the unavailability of health care. The Service Employees International Union Local 1877 said that workers at Cisco Systems, Hewlett-Packard, Yahoo Inc. and other tech companies will take part in the largest strike of its kind since 2000.

A spokesperson for the union that represents the janitors said the strike will continue and will grow each day, with more people threatening to join unless their demands are solved. Mike Garcia, president of the SEIU Local 1877 said the corporations need to do the right thing.

On average, janitors in San Jose area earn $11 per hour, while janitors in New York earn up to $20 per hour, the union unveiled, adding that the income is far from sufficient to support a family. Furthermore, the janitors complain that they are submitted to long waits before they are eligible for health care insurance.

None of the representatives of the tech companies whose names have been mentioned agreed to comment on the situation. Dave Miller, spokesman for  Applied Materials, told the San Francisco Chronicle that it is ultimately an issue that needs to be solved between the union and the employer contractors.

Jim Beard, chief negotiator for the cleaning companies, said that replacement workers have already been sent to clients’ facilities, adding that the employers had followed the framework of negotiations in Southern California, the same source reports.

The janitors demand for an extra $1.60 an hour over a four year period, less than in other places in the country, Mike Garcia announced. Beard said the 20 percent increase is in line with the agreement the union has reached for the rest of California.