Biological Hazards 생물학적 위험요소 - 3

Biological Hazards 생물학적 위험요소 - 3

 

 

▣ Biological Safety

 

 The primary objective of any biological safety program is to contain any harmful or potentially harmful biological agents from inside a controlled environment. The purpose of primary containment is to protect personnel and the immediate laboratory environment from exposure to infectious agents. The purpose of secondary containment is the protection of the environment outside of the laboratory. 

 There are three basic elements to a containment program, including laboratory practice and technique, safety equipment, and facility design.

 

 Biological safety program은 주로 실험실의 안전에 대해 다루며 주 목적은 잠재적으로 위험한 생물학적 위험요인들을 통제가 가능한 환경 내에 두는 것입니다. Primary containment의 목적은 사람과 실험실의 환경을 감염원으로부터 보호하는 것이고 Secondary containment의 목적은 실험실 외부환경을 보호하기 위한 것 입니다.

  Containment program에는 크게 ① laboratory practice and technique(실험실 규정 및 역량) ② safety equipment (안전 장비) ③ facility design (설비의 디자인) 으로 구분할 수 있습니다.

 

 

◈ Laboratory practice and technique (실험실 규정과 기술역량)

 

 Any laboratory working with hazardous or potentially hazardous agents should develop standard operating procedures in place prior to handling any hazardous agents. The procedures and practices should be strictly enforced at all times to prevent contamination or exposure. Employees working with these agents should be thoroughly trained and knowledgeable of these procedures, including emergency action plans.

 

 잠재적인 위험 요인(감염원)에 노출된 위험이 있는 실험실 작업환경은 위험요인들을 안전하게 다루기 위한 규정/절차 등이 마련되어야 합니다. 규정과 절차서는 감염원에 노출/오염을 방지하기 위하여 항상 철저하게 지켜질 수 있도록 해야하며, 감염원을 다루는 직원들은 철저하게 비상대책을 포함한 관련 교육을 받고 규정과 절차를 숙지하고 있어야 합니다.

 

규정내용들에 대해 몇가지 예를 들면 

• Limited and controlled access into the laboratory.
• Work areas, particularly horizontal surfaces, should be cleaned and decontaminated daily.
• Contaminated materials, including cleaning materials, should be decontaminated prior to disposal.
• Eating, drinking, smoking, or gum chewing should be strictly PROHIBITED inside the controlled area.
• Frequent hand washing should be enforced.
• Protective clothing should be worn to prevent contamination of street clothes.

등과 같은 것들이 있습니다.

 

 

 

◈ Safety equipment

 

 The basic safety equipment includes biological safety cabinets, personal protective equipment, and safety centrifuge cups. Biological safety cabinets are classified as Class I, Class II, or Class III.

 

 기본적인 안전 장비들에는 ① biological safety cabinet (생물 안전 작업대(캐비넷)), ② personal protective equipment (개인 보호구), ③ safety centrifuge cups. (안전 원심분리 컵) 등이 있으며, biological safety cabinet은 Class I, Class II, Class III로 등급을 구분합니다.

Biological safety cabinet (생물 안전 작업대)

Personal Protective Equipment

Safety centrifuge cup

 Biological safety cabinet의 Class I, Class II, Class III의 특징들을 살펴보면

 

  1) Class I

   - Room air flows through fixed front opening.

   - Approximately 8 inches.

   - Minimum velocity of 75 linear fpm

   - Prevents aerosols generated in cabinet from escaping to room.

   - Not appropriate for experimental systems vulnerable to airborne contamination.

 

 2) Class II

   - Protects the worker and research material.

   - Curtain of room air entering the grille at forward edge of opening to the work surface.

   - Partial recirculation of HEPA-filtered air

   - Downward flow of HEPA-filtered air creates contaminant-free zone.

 

 3) Class III (gas tight, negative pressure)

   - Provides physical barrier between agent and worker.

   - Highest degree of worker protection.

   - Arm-length rubber gloves and sealed front panel.

   - Air drawn into cabinet ghrough HEPA filtration.

 

 

◈ Facility Design and Construction (설비의 디자인 및 구성)

 

 Facility design and construction serves as secondary barriers. That is, the primary purpose is to prevent the escape of hazardous materials or agents outside of the controlled environment.

 

 설비의 디자인 및 구성은 감염원이 통제된 환경 외부로 빠져나가는 것을 막아주는 보조적인 차단역할을 해줍니다.

 

 

▣ Biosafety levels

 

 생물학적 위험요인들을 다루는 환경에는 위험도에 따라 Biosafety level의 등급을 구분하며 Biosafey level Ⅰ, Ⅱ, Ⅲ, Ⅳ로 나누어 집니다.

 

 

◈ Biosafey Level Ⅰ

 This level is appropriate for any undergraduate or secondary educational training laboratory.

 

◈ Biosafey Level Ⅱ

 The level of biosafety is adequate for most medical laboratory

 

◈ Biosafety Level Ⅲ

 This level of safety is adequate for laboratories that perform work on indigenous or exotic agents with a potential for respiratory transmission that may cause serious and potentially lethal infection.

 

◈ Biosafety Level Ⅳ

 The highest level of protection. Special engineering may be required and an air lock between the laboratory and public areas should be installed to prevent the escape of the hazardous agent.

 

Biosafety Level 구분

위 그림은 Biosafety level을 구분한 것으로 Level Ⅲ에 속하는 감염원들에는 teberculosis(결핵균), SARS-CoV-2 (코로나 바이러스), plague (페스트균) 등이 있으며 Level Ⅳ에는 Evola virus(에볼라), Smallpox virus(천연두)가 포함되어 있습니다.