噪聲(sheng)是發(fa)聲(sheng)體(ti)(ti)(ti)(ti)做無規則振動(dong)時發(fa)出的(de)(de)聲(sheng)音(yin)，聲(sheng)音(yin)由物體(ti)(ti)(ti)(ti)的(de)(de)振動(dong)產生，以(yi)波的(de)(de)形式在(zai)一定的(de)(de)介(jie)質(如固體(ti)(ti)(ti)(ti)、液體(ti)(ti)(ti)(ti)、氣體(ti)(ti)(ti)(ti))中(zhong)進行傳播通(tong)常所說的(de)(de)噪聲(sheng)污染是指人為造成的(de)(de)。產業革命以(yi)來，各種(zhong)機(ji)械設(she)備的(de)(de)創造和(he)使用，給人類帶來了(le)(le)繁榮和(he)進步，但同時也產生了(le)(le)越(yue)來越(yue)多而(er)且越(yue)來越(yue)強的(de)(de)噪聲(sheng)。

室內(nei)噪聲的主要來(lai)源：

1.交通運輸噪聲

城市(shi)交(jiao)通(tong)(tong)業(ye)日(ri)趨發(fa)達，給人們工作和(he)生(sheng)活帶來(lai)了便捷(jie)和(he)舒適，同時也(ye)促進了經濟的發(fa)展。但不(bu)能(neng)不(bu)看到(dao)，隨著城鄉車輛的增加，公(gong)路和(he)鐵路交(jiao)通(tong)(tong)干線(xian)的增多，機車和(he)機動車輛的噪(zao)聲已成了交(jiao)通(tong)(tong)噪(zao)聲的元(yuan)兇，占城市(shi)噪(zao)聲的75%。據(ju)統計表(biao)明，北京是世界有(you)名的噪(zao)聲污染城市(shi)。雖然城市(shi)車輛不(bu)及日(ri)本的十(shi)分(fen)之一， 噪(zao)聲程度卻比(bi)日(ri)本高出1倍。特別是一些臨街(jie)的建筑，受害極重。

2.工(gong)業(ye)機械環境噪(zao)聲

這也是室內(nei)噪(zao)(zao)聲污染(ran)的(de)(de)(de)主(zhu)要(yao)來源。由于(yu)各(ge)種動(dong)力(li)機(ji)、工(gong)作機(ji) 做(zuo)(zuo)功(gong)時產(chan)生的(de)(de)(de)撞擊、摩(mo)擦(ca)、噴射以及振動(dong)，可產(chan)生七(qi)八十分貝以上的(de)(de)(de)聲響。這些(xie)聲 響，像紡織車(che)間、鍛壓車(che)間、粉碎(sui)車(che)間和鋼(gang)廠、水泥廠、氣泵房(fang)、水泵房(fang)都(dou)比(bi)較嚴 重，雖然都(dou)做(zuo)(zuo)了一定(ding)程度(du)的(de)(de)(de)降噪(zao)(zao)處理，但仍然不能從根本上消除機(ji)器本體上所產(chan)生 的(de)(de)(de)噪(zao)(zao)聲。

3.建筑施(shi)工噪聲

建筑施(shi)(shi)工(gong)(gong)(gong)(gong)(gong)噪(zao)聲(sheng)是在工(gong)(gong)(gong)(gong)(gong)程(cheng)(cheng)建設(she)實施(shi)(shi)階段，包括基礎工(gong)(gong)(gong)(gong)(gong)程(cheng)(cheng)工(gong)(gong)(gong)(gong)(gong)程(cheng)(cheng)施(shi)(shi)工(gong)(gong)(gong)(gong)(gong)、主體(ti)結構施(shi)(shi)工(gong)(gong)(gong)(gong)(gong)、屋(wu)面(mian)工(gong)(gong)(gong)(gong)(gong)程(cheng)(cheng)施(shi)(shi)工(gong)(gong)(gong)(gong)(gong)、裝(zhuang)飾(shi)工(gong)(gong)(gong)(gong)(gong)程(cheng)(cheng)施(shi)(shi)工(gong)(gong)(gong)(gong)(gong)所產生的噪(zao)聲(sheng)(已竣工(gong)(gong)(gong)(gong)(gong)交付使用(yong)的住宅樓進行(xing)室內裝(zhuang)修(xiu)活(huo)動除外(wai))

噪(zao)聲(sheng)分為晝(zhou)間噪(zao)聲(sheng)和(he)夜間噪(zao)聲(sheng)

晝間噪聲時間：指6：00到(dao)22：00之間的(de)時段

夜間(jian)噪(zao)聲時(shi)間(jian)：指22：00到(dao)次日6：00之(zhi)間(jian)的時(shi)段