Aircraft Flight Operation Regulations Article 61
For an aerodrome to be selected as a take-off alternate, the available information shall indicate, that at least one hour before and one hour after the estimated time of arrival, the conditions will be at or above the aerodrome operating minima for that operation.
中文原文 航空器飛航作業管理規則第61條
當一機場被選作起飛備用機場時，該機場於航空器預計到達之前後一小時之天氣等有關資訊，應等於或高於機場最低飛航限度。