目前我国生产性粉尘的卫生标准有（）、总粉尘浓度和呼吸性粉尘容许浓度。

A.时间加权平均容许浓度 

B.工人接触时间肺总通气量 

C.粉尘浓度超标倍数

Which of the following home care activities would be appropriate for a client with a laryngectomy（）

A. Keep the stoma opening covered at all times.

B. Participate in activities such as walking and golfing.

C. Stay inside in an air-conditioned environment in the summer.

D. Avoid showering; take tub baths instead.