safety stock; buffer stock
Business and supply-chain term for extra inventory held to prevent stockouts caused by demand fluctuations or supply delays.
We secure safety stock in preparation for demand fluctuations.
We regularly review the level of safety stock.
在庫 is general 'inventory' or 'stock on hand'; 安全在庫 specifically refers to the buffer portion held to absorb uncertainty.
Compound of 安全 (safety) and 在庫 (inventory), likely a calque from English 'safety stock'.