The small exhaust air volume of the exhaust hood should be selected based on the larger value calculated as follows:

（1）按公式計(jì)算

(1) Calculated by formula

×P×

× P ×

式中L---排風(fēng)量，m3/h；

Where L - exhaust air volume, m3/h;

罩子的周邊長（靠墻側(cè)的邊不計(jì)），m；

The perimeter length of the cover (excluding the side against the wall), m;

罩口距灶面的距離，m。

The distance from the hood to the cooking surface, m.

（2）按罩口斷面的吸風(fēng)速度不小于0.5m/s計(jì)算的風(fēng)量。

(2) The air volume calculated based on the suction speed of the hood opening section not less than 0.5m/s.

廚房常用排風(fēng)罩有簡單傘形排風(fēng)罩、帶補(bǔ)風(fēng)的傘形排風(fēng)罩、洗滌式排煙罩。

The commonly used exhaust hoods in kitchens include simple umbrella shaped exhaust hoods, umbrella shaped exhaust hoods with supplemental air, and washing type smoke exhaust hoods.

（1）簡單排風(fēng)罩主要是吸走灶面上的上升氣流，罩內(nèi)裝有過濾器，過濾器常用的金屬網(wǎng)油霧過濾器面風(fēng)速一般控制在0.7~2.4m/s之間。

(1) The simple exhaust hood is mainly used to absorb the upward airflow on the surface of the stove. A filter is installed inside the hood. The commonly used metal mesh oil mist filter for filters has a surface wind speed generally controlled between 0.7 and 2.4 m/s.

（2）GB50189第4.4.5條規(guī)定，廚房熱加工間宜采用補(bǔ)風(fēng)式油煙排氣罩。帶補(bǔ)風(fēng)的傘形排風(fēng)罩一般送風(fēng)口風(fēng)速在0.50~1.0m/s之間，風(fēng)口形式多為可調(diào)式百葉送風(fēng)口；帶補(bǔ)風(fēng)的排風(fēng)罩效果較好的是向下送式。

(2) Article 4.4.5 of GB50189 stipulates that the kitchen thermal processing room should adopt a supplementary air type lampblack exhaust hood. Umbrella shaped exhaust hoods with supplemental air generally have a wind speed of 0.50-1.0 m/s at the air supply outlet, and most of the air outlets are adjustable shutter air supply outlets; The exhaust hood with supplementary air has a better effect, which is of the downwardly supplied type.

（3）洗滌式排煙罩是對排氣中除去熱、油煙、灰塵及氣味等，從灶具上抽出的帶油霧的空氣迅速地流經(jīng)風(fēng)機(jī)吸入口，而進(jìn)入排風(fēng)洗滌室，除油后將相當(dāng)干凈的空氣進(jìn)入排風(fēng)管道中。這種罩子在水壓為0.32MPa，水溫為19℃時(shí)，其除油效率為93%；除煙及除氣味效率為55%。罩內(nèi)裝有過濾器，過濾器應(yīng)便于清洗和更換，常用的金屬油過濾器過濾風(fēng)速一般控制在0.7~2.4m/s之間。

(3) The washing type smoke exhaust hood is used to remove heat, oil smoke, dust, and odors from the exhaust gas. The air with oil mist extracted from the stove quickly flows through the fan intake and enters the exhaust washing room. After oil removal, relatively clean air enters the exhaust duct. The oil removal efficiency of this cover is 93% when the water pressure is 0.32 MPa and the water temperature is 19 ℃; The efficiency of smoke and odor removal is 55%. The hood is equipped with a filter that should be easy to clean and replace. The filtering speed of commonly used metal oil filters is generally controlled between 0.7 and 2.4 m/s.

第6.3.5條，公共廚房通風(fēng)應(yīng)滿足以下規(guī)定：

Article 6.3.5 stipulates that the ventilation of public kitchens shall meet the following requirements:

（1）發(fā)熱量大且散發(fā)大量油煙和蒸汽的廚房設(shè)備應(yīng)設(shè)排氣罩等局部機(jī)械排風(fēng)設(shè)施；其他區(qū)域當(dāng)自然通風(fēng)達(dá)不到要求時(shí)，應(yīng)設(shè)置機(jī)械通風(fēng)。

(1) Local mechanical ventilation facilities such as exhaust hoods should be provided for kitchen equipment that generate large amounts of heat and emit large amounts of oil smoke and steam; In other areas, when natural ventilation cannot meet the requirements, mechanical ventilation should be provided.

（2）采用機(jī)械排風(fēng)的區(qū)域，當(dāng)自然補(bǔ)風(fēng)滿足不了要求時(shí)，應(yīng)采用機(jī)械補(bǔ)風(fēng)。廚房相對于其他區(qū)域應(yīng)保持負(fù)壓，補(bǔ)風(fēng)量應(yīng)與排風(fēng)量相匹配，且宜為排風(fēng)量的80%~90%。嚴(yán)寒和寒冷地區(qū)宜對機(jī)械補(bǔ)風(fēng)采取加熱措施。

(2) In areas where mechanical ventilation is used, when natural ventilation cannot meet the requirements, mechanical ventilation should be used. The kitchen should maintain a negative pressure relative to other areas, and the make-up air volume should match the exhaust air volume, preferably 80% to 90% of the exhaust air volume. Heating measures should be taken for mechanical air make-up in severe cold and cold areas.

（3）產(chǎn)生油煙設(shè)備的排風(fēng)應(yīng)設(shè)置油煙凈化設(shè)施，其油煙排放濃度及凈化設(shè)備的低去除效率不應(yīng)低于現(xiàn)行相關(guān)標(biāo)準(zhǔn)的規(guī)定，排風(fēng)口的位置應(yīng)符合該規(guī)范第6.6.18條的要求。

(3) The exhaust air of the equipment generating oil fume shall be equipped with oil fume purification facilities. The oil fume emission concentration and low removal efficiency of the purification equipment shall not be lower than the provisions of the current relevant national standards. The location of the exhaust outlet shall meet the requirements of Article 6.6.18 of this specification.

（4）廚房排油煙風(fēng)道不應(yīng)與防火排煙風(fēng)道共用。

(4) The kitchen oil smoke exhaust duct should not be shared with the fire and smoke exhaust duct.

（5）排風(fēng)罩、排油煙風(fēng)道及排風(fēng)機(jī)設(shè)置安裝應(yīng)便于油、水的收集和油污清理，且應(yīng)采取防止油煙氣味外溢的措施。

(5) The installation of exhaust hood, oil fume exhaust duct, and exhaust fan should facilitate the collection of oil and water and the cleaning of oil stains, and measures should be taken to prevent the overflow of oil fume odor.