厨房里有几类东西，不是等它明显坏掉才换，而是到了一定程度就该退役。下面这份清单给出的是判断标准，因为使用频率不同，单纯按时间并不准确。
砧板
判断标准：出现很深的刀痕（深到能卡住刀）、开裂、发霉、有异味、明显变形。塑料砧板刀痕太深时尤其要换，因为缝隙里很难彻底清洁。木质砧板养护得当可以用很多年。
抹布、洗碗布、海绵
判断标准：出现异味、变滑、发黏、洗不干净。
这几样是厨房里细菌最容易积聚的东西。建议：抹布每天清洗、定期用开水烫或煮沸消毒并彻底晾干；海绵和洗碗布一到两周更换一次，出现异味立刻换。
不粘锅
判断标准：涂层划伤见底、起皮脱落、明显粘锅。按通常使用频率，两三年更换一次比较常见，但关键还是看涂层状态。
塑料保鲜盒
判断标准：内壁出现明显划痕、发黄、洗不掉的油渍味、变形（尤其是加热后变形）。划痕深的塑料盒不适合再装油性、高温食物。
木质器具（木勺、木铲）
判断标准：开裂、起毛刺、发霉、表面发黏或有异味。木头吸味吸水，出现霉点就该换。
硅胶器具
判断标准：变形、开裂、发粘、变色、有异味。正常使用下寿命比木质器具长不少。
刀具
刀具一般不需要”定期更换”，而是靠磨刀维护。只有出现刀身开裂、刀柄松动无法修复、刃口有缺口难以磨平时，才考虑换新。
小家电（电水壶、料理机等）
判断标准：异常噪音、异味、漏水、加热异常、电源线破损。出现电气方面的异常应立即停用检修——这类问题不只是”不好用”，而是安全问题。
一条通用原则
如果一件器具已经很难彻底清洁干净，或者出现了影响安全的问题，那就是该换的信号。厨房器具的更新换代，本质上是为了卫生和安全，而不是为了新。
When to Replace Kitchen Items
Some kitchen items should be retired before they visibly break. Use condition, not a fixed calendar, as your guide.
- Cutting boards: replace when deeply scored, cracked, mouldy, odorous or warped. Deeply scratched plastic boards are hardest to clean properly.
- Cloths, sponges and scouring pads: replace at the first sign of odour or sliminess. Wash cloths daily and disinfect them with boiling water; replace sponges every one to two weeks.
- Non-stick pans: replace when the coating is scratched through, peeling or visibly sticking.
- Plastic food containers: replace when badly scratched, stained, permanently smelly or warped — especially after heating.
- Wooden utensils: replace when cracked, splintered, mouldy or tacky to the touch.
- Silicone utensils: replace when warped, cracked, tacky, discoloured or odorous.
- Knives: maintained by sharpening rather than replaced, unless the blade is cracked, the handle cannot be tightened, or the edge is chipped beyond repair.
- Small appliances: stop using and have them inspected at any sign of abnormal noise, smell, leakage or damaged wiring — these are safety issues, not inconveniences.
The general rule: if it can no longer be cleaned properly, or if it raises a safety concern, it is time to replace it.