The Fairfax County Board of Supervisors is asking Gov. Terry McAuliffe to reject a proposed requirement that all child-care providers who receive government subsidies — both in centers and at home day cares — should be able to speak, read and write in English.

The proposed change, which would expand an existing language requirement and would affect more than 3,000 providers serving about 34,000 children, is one of multiple changes geared toward improving safety and consistency in child-care settings. The requirement says that workers should have English skills sufficient to "understand the regulations and communicate with emergency service personnel, parents and children, the department and local department personnel."

Margaret Schultze, commissioner of the department of social services in Virginia, said English proficiency is a "quality of care issue because it deals with the health and safety of the children we are caring for."

"If a child is in distress, a provider may need to read instructions to properly administer a medication or be able to communicate with the folks that are responding to an emergency," she said. Schultze stressed that the proposed regulation, which was given preliminary approval in June by the State Board of Social Services, is still under review. After the regulations are approved by the governor, there will be a public comment period and a public hearing.

Officials in Fairfax say the English requirement would have an opposite effect on children's safety by driving many immigrant day-care operators underground.

"We spend a lot of time and effort in Fairfax County encouraging all day-care providers to be licensed. This will encourage day-care providers to not participate," said Supervisor Jeff C. McKay (D-Lee).

More broadly, he said, an English requirement would affect the affordability and availability of child care in Northern Virginia: "Why do you want to limit the pool of people who can work in already stressful, difficult jobs with high turnover and low wages?"

The Fairfax supervisors sent a letter to Gov. McAuliffe (D) this week asking him not to approve the English language requirement, or if it is adopted, to grant Fairfax County a waiver.

Virginia, along with other states, is updating its regulations to reflect new federal rules adopted in 2014 that govern the grant program that subsidizes child care for many low-income families.

The federal rules do not require English proficiency. The Fairfax board's letter to the governor notes that the federal regulations actually encourage states to support providers who are learning English and to "respect and support children's home language and culture."

Most states are moving to make their child-care programs more responsive to diverse families and to improve the skills of a linguistically diverse workforce, advocates say. Training for the nationally recognized Child Development Associate (CDA) certificate, considered a baseline credential in the field, is offered in multiple languages.

"What research shows us is that it's the quality of interactions between a caregiver and a child that make a difference, not what language they are speaking," said Yvette Sanchez Fuentes, deputy chief of public policy and research at Child Care Aware of America.

Some advocates fear that an English proficiency requirement could alienate many of the low-income immigrant families that could benefit from the federally subsidized child-care program because there would be fewer operators that speak their languages and they might seek out unlicensed care providers instead.

Danny Avula, a physician and chairman of the Board of Social Services in Virginia, said that the revised regulations also must take the needs of immigrant communities into account and balance them with safety considerations.

"There are obviously growing communities in Virginia that do not speak English. We need to figure out how to best support those communities," he said.

Just a handful of other states have rules that mention English proficiency at all, according to an analysis by Child Care Aware of America.

Oklahoma requires three credit hours of English composition for some child-care program directors, and Utah and Tennessee expect that at least one provider speak English whenever children are present in a child-care center. Tennessee also requires primary care providers in home day cares to read and write in English.

Nevada's rules say that child-care facilities must have as part of their curriculum "a program of speaking and listening to English," but it also requires facilities to employ staff that can communicate with families who speak a language other than English.

In Virginia, an English-language requirement has long been in place for family day-care providers serving five or more children, which are licensed by the state. Schultze said expanding the language proficiency requirement is partly an effort to make the licensing standards more consistent across different types of child-care settings in the state.

Virginia's proposed regulations for the federal program would expand the current language requirement to make it effective for any child-care provider that receives subsidies, including smaller home providers that are regulated locally. English proficiency would be verified during new annual state health and safety inspections.

Fairfax County, as well as Arlington and Alexandria, have their own systems for regulating small home day cares serving four or fewer children.

Anita Friedman, director of the department of human services for Arlington County, said the county does not require English proficiency for small home-care providers but it does conduct most of its business in English, and the county would potentially not extend a license to an operator with very limited English abilities due to safety concerns.

But, she said, "by writing it into the code, you are drawing a firm line in the sand, and you get into the issue of how much English is enough." She said she would be sorry to lose a very good child-care provider whose English may be "shaky."

Fairfax County does not have a language requirement and offers technical assistance to small in-home child-care providers in multiple languages so they can comply with all local, state and federal laws, according to the board's letter to the governor.

"Our goal has been to bring providers into the regulatory system and support them in providing safe care," Anne-Marie Twohie, director at Fairfax County's office for children, said in an interview.

She said that county-permitted home providers have health and safety visits twice a year, an annual visit from the fire department and professional development in multiple languages.

"It's always been in the spirit of promoting safe, quality environments," she said.