噪聲(sheng)是(shi)發聲(sheng)體(ti)做無規則振(zhen)動時發出的(de)聲(sheng)音，聲(sheng)音由(you)物體(ti)的(de)振(zhen)動產生，以波的(de)形(xing)式(shi)在(zai)一定的(de)介(jie)質(如固體(ti)、液體(ti)、氣體(ti))中進行傳播通常所說的(de)噪聲(sheng)污染是(shi)指人為造(zao)成的(de)。產業革命以來，各(ge)種機械(xie)設備的(de)創造(zao)和使(shi)用(yong)，給人類帶來了繁榮和進步，但(dan)同時也產生了越來越多而(er)且越來越強的(de)噪聲(sheng)。

室(shi)內噪聲的主要(yao)來源：

1.交(jiao)通運輸(shu)噪聲

城(cheng)市交通(tong)業(ye)日趨發(fa)達，給人們工(gong)作和生活帶來了便(bian)捷和舒適，同時也(ye)促進了經濟的(de)發(fa)展。但不能不看到(dao)，隨著城(cheng)鄉車(che)輛的(de)增加(jia)，公路(lu)和鐵路(lu)交通(tong)干線的(de)增多，機(ji)車(che)和機(ji)動車(che)輛的(de)噪(zao)聲(sheng)已成(cheng)了交通(tong)噪(zao)聲(sheng)的(de)元兇，占城(cheng)市噪(zao)聲(sheng)的(de)75%。據統(tong)計(ji)表明，北京(jing)是世(shi)界有名的(de)噪(zao)聲(sheng)污染城(cheng)市。雖然城(cheng)市車(che)輛不及日本的(de)十分(fen)之一， 噪(zao)聲(sheng)程度卻比(bi)日本高(gao)出1倍(bei)。特(te)別是一些臨街的(de)建筑，受害極重。

2.工業(ye)機械(xie)環(huan)境噪聲(sheng)

這也是(shi)室內(nei)噪聲(sheng)(sheng)污染的主(zhu)要來源。由于各種動(dong)力機(ji)(ji)、工作機(ji)(ji) 做功(gong)時(shi)產生的撞擊、摩擦、噴射以(yi)及振動(dong)，可產生七八十分(fen)貝以(yi)上(shang)的聲(sheng)(sheng)響(xiang)。這些聲(sheng)(sheng) 響(xiang)，像紡織車間、鍛壓車間、粉(fen)碎車間和鋼廠、水泥廠、氣泵房、水泵房都(dou)比較(jiao)嚴 重，雖然(ran)都(dou)做了一定程度的降(jiang)噪處(chu)理，但仍然(ran)不能從根本上(shang)消除機(ji)(ji)器本體上(shang)所(suo)產生 的噪聲(sheng)(sheng)。

3.建筑施(shi)工(gong)噪聲

建筑(zhu)施工(gong)(gong)(gong)(gong)(gong)(gong)噪(zao)(zao)聲是在(zai)工(gong)(gong)(gong)(gong)(gong)(gong)程(cheng)建設實施階段，包括基(ji)礎工(gong)(gong)(gong)(gong)(gong)(gong)程(cheng)工(gong)(gong)(gong)(gong)(gong)(gong)程(cheng)施工(gong)(gong)(gong)(gong)(gong)(gong)、主體結構施工(gong)(gong)(gong)(gong)(gong)(gong)、屋面工(gong)(gong)(gong)(gong)(gong)(gong)程(cheng)施工(gong)(gong)(gong)(gong)(gong)(gong)、裝飾工(gong)(gong)(gong)(gong)(gong)(gong)程(cheng)施工(gong)(gong)(gong)(gong)(gong)(gong)所產生的噪(zao)(zao)聲(已竣工(gong)(gong)(gong)(gong)(gong)(gong)交付使(shi)用(yong)的住宅(zhai)樓進行室(shi)內(nei)裝修活動除外)

噪(zao)聲分為晝間(jian)噪(zao)聲和夜間(jian)噪(zao)聲

晝(zhou)間(jian)噪聲時(shi)間(jian)：指6：00到22：00之間(jian)的時(shi)段

夜間噪(zao)聲(sheng)時間：指(zhi)22：00到次(ci)日6：00之間的時段