A group representing major US chipmakers said it was working with federal authorities to make clear to state and local quarantine authorities that chip production is an essential business that must continue to operate.

In a blog post, the Semiconductor Industry Association, which represents large-scale US manufacturers such as Intel and Micron Technology, says it is working with the Department of Homeland Security to refine guidance sent to state and local governments last week.

This guide mentions semiconductor manufacturers as an essential business because of their role in supporting information technology, which became especially important at a time when millions of Americans were working from their homes. John Neuffer, the group’s president, said in a blog post that semiconductors also play an important role in medical equipment, electrical networks, and other necessary infrastructure.

“Ensuring business continuity for chip companies and related supply chains is needed to support an even greater range of services that will be digitized over the coming weeks and months”, writes John Neuffer. “Because the chip supply chain is highly globalized, the scarcity of chips created by job restrictions in one region cannot be easily offset by production in others”, added he.

To date, the major chipmakers in the United States have not announced a shutdown. Last week, the CEO of Intel, Bob Swan, indicated in a letter to company employees that factories, including those in California, Oregon, New Mexico, and Arizona, “keep speeds up to over 90% of deliveries at the moment”.

Sanjay Mehrotra, CEO of Micron Technology, which operates factories in Utah, Idaho, and Virginia, said last week in a letter that the company was “carefully managing the raw materials and its supply chain to maintain its manufacturing capabilities”.

But on Wednesday, Mehrotra revealed that a March 16 order restricting the movement of Malaysian citizens had hit the company’s plants in Muir and Penang, which were “closed for a while” before authorities announced it was a key business. According to him, the factories have since “been able to return to production on a very limited basis, in accordance with local regulations”.