Amazon said Tuesday that it will only accept shipments from suppliers of cleaning equipment, medical supplies and household goods at its warehouses for the next three weeks to fill surging demand. It is hiring 100,000 people across the U.S. to keep up with a crush of orders as more people stay at home and shop online. It will also temporarily raise pay by $2 an hour through the end of April for hourly employees.

Many grocers are also limiting purchases of products like Purell sanitizers, Lysol cleaning spray and canned soup so that there is enough to go around. And companies like Walmart, Target and Wegman’s are curbing store hours for the public in order to give workers time to restock shelves.

The moves come as industry executives insist supply chains remain strong despite frustrated customers showing up to stores and sometimes walking away empty-handed.

“When you have runs at grocery stores, there is a little time needed to catch up,” said Lowell Randel, vice president for government and legal affairs at the Global Cold Chain Alliance, a trade group representing the refrigerated warehouse and delivery industry.