• 제목/요약/키워드: Cross-contamination

검색결과 264건 처리시간 0.031초

Issues of Halal Supply Chain Management: Suggestion for Korean Traders

  • Lee, Hee-Yul;Hwang, Hyun-Ju;Kim, Dong-Hwan
    • Journal of Korea Trade
    • /
    • 제23권8호
    • /
    • pp.132-144
    • /
    • 2019
  • Purpose - The purpose of this paper is to suggest countermeasures to reduce the damage of manufacturers in halal industries and to increase the transparency of the halal market along with raising some problems of halal supply chain management (HSCM). Design/methodology/approach - To achieve to the aim of this research, halal supply chain is categorized as a green zone or a red zone according to the possibility of cross-contamination, and the study introduces 2 examples in Malaysia and Indonesia regarding cross-contamination. Findings - More than 70% of the companies producing halal-certified products are, ironically, non-Muslim suppliers under the halal certificate system and by using halal supply chain. Most Muslim countries do not exercise control over the completed halal supply chain. In most Muslim countries which do not exercise control over halal supply chain properly, there is always a possibility of cross-contamination of products during the processes of distribution. Research limitations/implications - This research has been conducted by accessing cases in halal supply chain. These cases are found in some Muslim countries, not all Muslim countries. Nevertheless, the authors found the possibility of these cross-contaminations in all Muslim countries, and it will damage the halal market. Originality/value - While existing studies have focused on protecting Muslim consumers by ensuring the integrity of halal products in halal supply chain, there is no research on how to protect halal product manufacturers as another important axis of halal SCM.

덴탈유니트의 핸드피스 및 초음파 치석 제거기의 미생물 오염에 관한 연구 (A STUDY ON THE MICROBIAL CONTAMINATION OF DENTAL UNIT AND ULTRASONIC SCALER)

  • 이병문;김창회;김영수
    • 대한치과보철학회지
    • /
    • 제36권1호
    • /
    • pp.64-80
    • /
    • 1998
  • The risk of cross-contamination in dental clinic is very high. Those who are engaged in dental clinic are exposed to various microorganisms in saliva and blood of patient. Potential possibility of cross-contamination of patient to patient, patient to dentist, dentist to laboratory technician always exist, which is important in the view of public health. It is well known that microorganisms may cause cross-contamination by suck-back of microorganisms into the water supply line or air supply line of dental unit and sprayed back into the next patient's oral cavity. The majority of microorganisms coming from dental unit are water microorganisms from the main water supply which have colonized the tube within the units and multiplied in the relatively warm and stagnant conditions. The purpose of this study is to measure the extent of microbial contamination of dental unit and ultrasonic scaler, to evaluate that dental unit water supply is suitable for drinking water, and to assess the effect of flushing on reduction of microbial contamination of dental unit and ultrasonic scaler. In the first experiment, water samples(50ml) from 20 dental units and 10 ultrasonic scalers in Seoul National Univ. Hosp. were tested for the presence of coliform. The samples were filtered by membrane filtration technique.(Microfil system, Millipore Co. U. S. A.) The filter was then placed onto MacConkey agar plate and the plates with filter on it were incubated aerobically at $37^{\circ}C$ for 5 days. The colors and shapes of colonies were examined if those were coliform. To verify the presence of coliform, the colonies were inoculated into phenol red lactose broth and incubated aerobically at $37^{\circ}C$ for 2 days. The fomation of gas was observed. In the second experiment, water samples from 20 handpieces, 10 ultrasonic scalers and 30 A/W syringes after 0, 2, 4, 6 min. flushing respectively were taken. $200{\mu}l$ water samples were spreaded on Brain Heart Infusion agar plate and the plates were incubated aerobically at $37^{\circ}C$ for 5 days. The number of colony was counted. The results obtained were summarized as follows 1. The water from dental unit and ultrasonic scaler was not suitable for drinking water. 2. No coliform was founded in dental unit and ultrasonic scaler water supply. 3. The number of colony of dental unit and ultrasonic scaler was highest in the group of o min. flushing(p<0.05). 4. There was no statistically significant difference in the extent of microbial contamination among handpiece, ultrasonic scaler and A/W syringe (p>0.05). 5. The number of colony was lowest in the group of 4 min. flushing, but there was no statistically significant difference among 2, 4, 6 min. flushing groups.(p>0.05) 6. It is recommended to flush dental unit water line for 4 min. after use on each patient.

  • PDF

Choosing Optimal STR Markers for Quality Assurance of Distributed Biomaterials in Biobanking

  • Chung, Tae-Hoon;Lee, Hee-Jung;Lee, Mi-Hee;Jeon, Jae-Pil;Kim, Ki-Sang;Han, Bok-Ghee
    • Genomics & Informatics
    • /
    • 제7권1호
    • /
    • pp.32-37
    • /
    • 2009
  • The quality assurance (QA) is of utmost importance in biobanks when archived biomaterials are distributed to biomedical researchers. For sample authentication and cross-contamination detection, the two fundamental elements of QA, STR genotyping is usually utilized. However, the incorporated number of STR markers is highly redundant for biobanking purposes, resulting in time and cost inefficiency. An index to measure the cross-contamination detection capability of an STR marker, the mixture probability (MP), was developed. MP as well as other forensic parameters for STR markers was validated using STR genotyping data on 2328 normal Koreans with the commercial AmpFlSTR kit. For Koreans, 7 STR marker (D2S1338, FGA, D18S51, D8S1179, D13S317, D21S11, vWA) set was sufficient to provide discrimination power of ${\sim}10^{-10}$ and cross-contamination detection probability of ${sim}1$. Interestingly, similar marker sets were obtained from African Americans, Caucasian Americans, and Hispanic Americans under the same level of discrimination power. Only a small subset of commonly used STR markers is sufficient for QA purposes in biobanks. A procedure for selecting optimal STR markers is outlined using STR genotyping results from normal Korean population.

소방 방화복 교차오염 저감 및 관리체계 개선을 위한 델파이 연구 (Delphi Study on the Reduction of Cross-contamination and Improvement of Management System on Firefighting Protection Suit)

  • 김수진;함승헌
    • 한국산업보건학회지
    • /
    • 제32권2호
    • /
    • pp.182-194
    • /
    • 2022
  • Objectives: This study evaluates and recommends the priority of policy implementation to improve the fire protection clothing management system used by firefighters and the reduction of cross-contamination from contaminated clothing at the scene of a fire. Methods: It consisted of 7 experts and conducted three interviews and two modified Delphi surveys. Through the results of previous research and interviews with experts, a plan to reduce cross-contamination of fire suits and improve the management system was first derived. An improvement plan was presented in the four areas including resources, management, fire protection related work, and laws and regulations, and the priority of policy implementation was derived by analyzing the importance and practicality of the policy at the same time. Results: As a result of the analysis, the first priority was education on the health effects of pollutants at the disaster scene for firefighters, and the second priority was the addition of SOP for the primary decontamination of on-scene personal protective equipment in preparation for the health effects of the disaster scene, and education for fire suppression and rescue workers. The next step was to improve the management system of personal protective equipment such as fire suits and develop a training course for systematic operation. Conclusions: This findings could be used in the implementation of mid- to long-term firefighting policies for the systematic operation and establishment of a systematic management system for personal protective equipment such as fire protective suits.

원재료, 조리기구와 조리원 손에 의한 급식소 조리음식의 미생물오염 실태 분석 (Analysis of Contamination of Bacteria from Raw Materials, Utensils and Workers' Hands to Prepared Foods in Foodservice Operations)

  • 배현주
    • 한국식품영양과학회지
    • /
    • 제35권5호
    • /
    • pp.655-660
    • /
    • 2006
  • 급식규모와 운영형태가 유사한 3곳의 급식소를 대상으로 원재료, 조리기구 및 조리종사원 손과 최종조리음식간의 미생물 오염실태를 분석한 결과는 다음과 같다. A 급식소에서는 닭볶음탕, 잡채, 비빔밥, 콩나물무침에서 황색포도상구균이 검출되었다. 닭볶음탕은 조리종사원의 손, 재료를 손질한 도마, 양파에서 황색포도상구균이 검출되었으므로 조리종사원의 손이나 도마를 통한 교차오염이 발생한 것으로 판단된다. 잡채는 조리종사원의 손, 당면을 삶아 건진 바구니, 양파와 양파를 손질한 도마에서 모두 황색포도상구균이 검출되었으므로 이들 간의 교차오염이 발생했을 것으로 생각된다. 비빔밥과 콩나물무침은 해당일 조리를 담당한 종사원의 손에서 황색포도상구균이 검출되었으므로 조리종사원 손에 의한 오염이 발생한 것으로 판단된다. B 급식소의 쥐어채조림은 원재료의 황색포도상구균이 조리과정에서 그대로 전이되어 조림 후에도 검출되었다. C급식소의 오징어채무침에서는 대장균이 검출되었다. 오징어채무침은 가열조리공정을 거치지 않는 메뉴로서 원재료인 오징어채에서 검출되었던 대장균이 그대로 최종조리 후까지 전이된 것으로 판단된다. 급식소 최종음식의 안전성 확보를 위해서는 위생적인 원재료의 구매와 사용, 조리종사원 개인위생의 개선, 조리기기의 철저한 세척 및 소독관리가 선행되어야 할 것으로 사료된다.

Effect of Brush Treatment and Brush Contact Sequence on Cross Contaminated Defects during CMP in-situ Cleaning

  • Kim, Hong Jin
    • Tribology and Lubricants
    • /
    • 제31권6호
    • /
    • pp.239-244
    • /
    • 2015
  • Chemical mechanical polishing (CMP) is one of the most important processes for enabling sub-14 nm semiconductor manufacturing. Moreover, post-CMP defect control is a key process parameter for the purpose of yield enhancement and device reliability. Due to the complexity of device with sub-14 nm node structure, CMP-induced defects need to be fixed in the CMP in-situ cleaning module instead of during post ex-situ wet cleaning. Therefore, post-CMP in-situ cleaning optimization and cleaning efficiency improvement play a pivotal role in post-CMP defect control. CMP in-situ cleaning module normally consists of megasonic and brush scrubber processes. And there has been an increasing effort for the optimization of cleaning chemistry and brush scrubber cleaning in the CMP cleaning module. Although there have been many studies conducted on improving particle removal efficiency by brush cleaning, these studies do not consider the effects of brush contamination. Depending on the process condition and brush condition, brush cross contamination effects significantly influence post-CMP cleaning defects. This study investigates brush cross contamination effects in the CMP in-situ cleaning module by conducting experiments using 300mm tetraethyl orthosilicate (TEOS) blanket wafers. This study also explores brush pre-treatment in the CMP tool and proposes recipe effects, and critical process parameters for optimized CMP in-situ cleaning process through experimental results.

Prevention of P-i Interface Contamination Using In-situ Plasma Process in Single-chamber VHF-PECVD Process for a-Si:H Solar Cells

  • Han, Seung-Hee;Jeon, Jun-Hong;Choi, Jin-Young;Park, Won-Woong
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 2011년도 제40회 동계학술대회 초록집
    • /
    • pp.204-205
    • /
    • 2011
  • In thin film silicon solar cells, p-i-n structure is adopted instead of p/n junction structure as in wafer-based Si solar cells. PECVD is a most widely used thin film deposition process for a-Si:H or ${\mu}c$-Si:H solar cells. For best performance of thin film silicon solar cell, the dopant profiles at p/i and i/n interfaces need to be as sharp as possible. The sharpness of dopant profiles can easily achieved when using multi-chamber PECVD equipment, in which each layer is deposited in separate chamber. However, in a single-chamber PECVD system, doped and intrinsic layers are deposited in one plasma chamber, which inevitably impedes sharp dopant profiles at the interfaces due to the contamination from previous deposition process. The cross-contamination between layers is a serious drawback of a single-chamber PECVD system in spite of the advantage of lower initial investment cost for the equipment. In order to resolve the cross-contamination problem in single-chamber PECVD systems, flushing method of the chamber with NH3 gas or water vapor after doped layer deposition process has been used. In this study, a new plasma process to solve the cross-contamination problem in a single-chamber PECVD system was suggested. A single-chamber VHF-PECVD system was used for superstrate type p-i-n a-Si:H solar cell manufacturing on Asahi-type U FTO glass. A 80 MHz and 20 watts of pulsed RF power was applied to the parallel plate RF cathode at the frequency of 10 kHz and 80% duty ratio. A mixture gas of Ar, H2 and SiH4 was used for i-layer deposition and the deposition pressure was 0.4 Torr. For p and n layer deposition, B2H6 and PH3 was used as doping gas, respectively. The deposition temperature was $250^{\circ}C$ and the total p-i-n layer thickness was about $3500{\AA}$. In order to remove the deposited B inside of the vacuum chamber during p-layer deposition, a high pulsed RF power of about 80 W was applied right after p-layer deposition without SiH4 gas, which is followed by i-layer and n-layer deposition. Finally, Ag was deposited as top electrode. The best initial solar cell efficiency of 9.5 % for test cell area of 0.2 $cm^2$ could be achieved by applying the in-situ plasma cleaning method. The dependence on RF power and treatment time was investigated along with the SIMS analysis of the p-i interface for boron profiles.

  • PDF

Reduction of Microflora in the Manufacture of Saengshik by Hygienic Processing

  • Bang, Woo-Seok;Eom, Young-Rhan;Oh, Deog-Hwan
    • Preventive Nutrition and Food Science
    • /
    • 제12권3호
    • /
    • pp.167-172
    • /
    • 2007
  • This study was conducted to determine the effect of hygienic processing (HP) on the reduction of microorganisms during manufacturing of saengshik with two vegetables (carrots and cabbage) and two grains (barely and glutinous rice) compared to general processing (GP). For GP, distilled water was used for washing raw materials and equipment. For HP, aqueous ozone (3 ppm) in combination with 1% citric acid and 70% alcohol were used for washing raw materials and the equipment, respectively. In carrots, after cutting, total aerobic bacteria (TAB), yeast and mold (YM) and coliforms were significantly increased to 5.19, 8.04 and 2.08 ($log_{10}$ CFU/g), respectively (p<0.05). Washing effectively reduced the increased microorganisms from cross contamination during cutting, but cross contamination increased with subsequent GP drying and milling procedures to 8.56, 8.27 and 3.71 ($log_{10}$ CFU/g) for TAB, YM and coliforms, respectively (p<0.05). On the other hand, HP washing of carrots with 3 ppm ozone in combination with 1% citric acid showed higher antimicrobial effect than GP washing, significantly decreasing the number of microorganisms (p<0.05). Further cross contamination did not occur through drying and milling due to cleaning the equipments with 70% alcohol prior to processing. After milling, the number of TAB, YM and coliforms were significantly decreased to 3.89, 4.47 and not detectable level ($log_{10}$ CFU/g), respectively (p<0.05). Similar results were observed in cabbage and grains. During storage for two months at different temperatures (22 or $4^{\circ}C$), there were no changes in numbers of spoilage microorganisms in the packaged saengsik after either processing. This suggests the importance of HP for the reduction of microorganisms during saengsik production, and demonstrates the effectiveness of disinfection at each processing stage in minimizing contamination levels to enhance microbial safety of saengshik products.

HACCP를 적용한 셀프서비스 식당의 위생적 공간구성에 관한 연구 (A Study on Hygienic Spatial Composition of Self-Service Restaurants by Applying HACCP)

  • 이종란
    • 한국실내디자인학회논문집
    • /
    • 제20권5호
    • /
    • pp.178-187
    • /
    • 2011
  • This research suggested the hygienic spatial composition of sell-service restaurants applying HACCP(Hazard Analysis and Critical Control Point System). The circulation of the food, dishes, waste, workers and customers were each fractionated and arranged according to the hygienic sequence of cooking food in kitchen and process for eating food within the customer space. The spaces were separated by the degree of cleanness(clean area, semi-clean area, contaminated area). After that, hygiene facilities to remove contamination and pass facilities intended to control moving were added at the possible points of cross-contamination in oder to prevent the cross-contamination. For hygienic spatial composition of self-service restaurant, the following should be acknowledged: In the kitchen, spaces in which the food is handled after being heated should be located in the clean area. As of the customer space, spaces where dishes are prepared, food and water is received, and the table hall should be located in the clean area. Food circulation should flow from the contaminated area to the clean area. Food, dishes, waste should be moved through pass facilities so that workers do not have to come and go between other areas of cleanness. Also lockers for private clothes and lockers for uniforms should be separated. Hygiene facilities should be easily accessible so that workers can use them whenever they enter their working area. The contaminated area where dirty dishes are dealed with should be separated from the clean area. Waste should be thrown out without crossing cooking areas. As of customer circulation, the hygiene facility for hand washing should be located near the space where dishes for self-service are placed. The customer circulation should lead customers to leave restaurants after giving back the dirty dishes in the contaminated area.