Intercomparison of Gamma Cell 220 Irradiator Facilities and Dr. Mirzan T Razzak Gamma Irradiators Using Harwell Dosimeters

The gamma irradiator is a multi-purpose facility that possibly used to preserve food, sterilize medical equipment, and conduct genetic engineering and polymerization processes, during which the absorbed dose of the product is critical. The standardization of product quality assurance was regulated by the IAEA Technical Document Number 409 considering Dosimetry for Food Irradiation and ISO 14470 and 11137-3 on Food Irradiation, as well as the Guidance on Dosimetric Aspects of Development, Validation, and Routine Control, respectively. The absorbed dose was influenced by the movement of the product to the source, its position, the amount of radioactive activity in the facility, and the dose rate in the irradiation room. The dosimeter performance test and quality assurance of the system were conducted using the Facility Intercomparison Technique which tested the dosimeter (measuring instrument) at 2 different facilities to determine the performance of the measuring instrument.. In this study, 2 irradiation facilities were tested using a Harwell routine dosimeter in the dose range of 1 kGy to 30 kGy and 20 dose points. The results showed that the highest deviation reached 19% and 21% at the Gamma Cell 220 and the Dr. Mirzan T Razzak Gamma irradiator facilities. This elevated the performance of the dosimeters to determine the precision accuracy of the dose-measuring instrument.

Calculation of critical core configurations of a research reactor using MTR, IRT-4M, VVR-KN fuel assemblies

This paper presents calculation results to determine critical core configurations and aminimum number of fuel assemblies (FAs) or uranium mass of a research reactor loaded with three types of FAs such as MTR, IRT-4M and VVR-KN. The MCNP5 code and ENDF/B7.1 library were applied to estimate characteristics parameters of the fuel types and the whole core. Infinitive multiplication factor kinf, neutron flux distribution and neutron spectra of the fuels were calculated. The reactor core configurations with three fuel types were modeled in 3-dimensions, and then the effective multiplication factors keff, relative radial power distribution of each configuration were also evaluated. From calculation results, twelve fuel loading schemes were chosen based on lowest uranium mass or smallest number of FAs loaded into the core. In addition, two full core configurations using VVR-KN and MTR FAs and consisting of beryllium reflectors, vertical irradiation facilities, horizontal neutron beam ports, etc. have been proposed for further consideration in thermal hydraulic calculations and safety analysis.

Regulatory Approach for Transitioning from Gamma Ray to X-ray Radiation Sterilization

When investing in X-ray irradiation facilities around the world, an opportunity exists for defining a regulatory framework for assessing the transition from current gamma irradiation processes. Historically, regulatory strategies for changing the radiation source for routine processing has consisted of repeating the majority, if not all, of the validation activities performed as part of an initial validation and associated submission. Although not a new concept, performing a risk assessment has the potential to be leveraged more fully by increasing the rigor of determining what is changing when product moves from a gamma to an X-ray irradiator, then determining how these differences may affect product characteristics. During these steps, differences can be identified and quantified between radiation sources and potential impacts, if any, to product quality can be elucidated. Based on these risk assessments, the level of action required, or not required, in terms of empirical product testing can be examined and a determination can be made regarding whether a substantial change has occurred.

PEMBUATAN PIRANTI “URUP-URIP” PENYINARAN UV BERTENAGA SURYA: UPAYA STERILISASI BAKTERI PADA HASIL PANEN TANAMAN SAYUR DI CIANJUR, JAWA BARAT

<p>The problems generally faced by farmers are that vegetables easily rotting due to delayed selling time and higher hygienic standard of vegetables. Based on an interview, we acknowledge that the farmers are unable to understand the utilization of ultraviolet irradiation technology. UV irradiation facilities - which help kills various types of bacteria, spores, protozoan viruses and algae - should be placed near vegetable harvest location. The physical part of vegetables requires special attention and they should not be moved on a regular basis to prevent damages. However, the harvest location is quite distant from electricity sources. As a solution to overcome this problem, a solar powered UV irrayer facility equipped with a portable bag is required. Besides that, the tool should be fitted with branded plastic casings to hold the vegetable to improve selling value, safety, and readiness of the vegetables. The objective of the utilization of this appropriate technology is to improve the quality of the harvested crops. Vegetables will be free from bacteria and risks of Covid-19 exposures. The target of this program is to improve vegetable selling sales rate and to improve the prosperity of the farmers better, or at least as high as pre-pandemic era. The method used to procure this appropriate technology is a design thinking method that covers empathy, define, ideate, prototype, and testing. The implementation of the counseling and training activities were conducted on-line and off-line whilst also applying a strict health protocol. The activity was conducted for 4 months.</p>

Comparative Assessment of Sodium and LED Greenhouse Irradiators Main Characteristics

The authors showed that traditional sodium greenhouse irradiators are being replaced by more efficient LED ones. (Research purpose) To conduct a comparative assessment of the main characteristics of sodium and LED greenhouse irradiators with an equal photosynthetic photon flux. (Materials and methods) The authors collected a database of 79 sodium irradiators (34 irradiators with electronic ballasts and 45 – with electromagnetic) and 118 – LED. A comparative assessment was carried out in two stages. At the first stage mathematical models of the power, mass, area and cost of irradiation facilities dependence on the photosynthetic photon flux generated by them were obtained. At the second stage the system of equations of sodium and LED greenhouse irradiators for each characteristic were solved. (Results and discussion) The consumed active power of LED irradiators is on average 33 percent less compared to sodium. The area of LED illuminators is 2.5 times larger than sodium irradiators with electronic ballast and 44 percent more than sodium irradiators with electromagnetic ballast. The LED irradiators mass is 3.5 times more than sodium with electronic ballast and 20 percent more than sodium with electromagnetic ballast. The cost of LED illuminators is 3.5 and 4.3 times higher. (Conclusions) LED irradiators are more energy efficient compared to sodium ones. However, due to the high cost, their implementation requires a feasibility study, including additional evaluation criteria: service life, operating costs, electricity price and others.

JSI TRIGA neutron and gamma field characterization by TLD measurements

A well characterized radiation field inside a research nuclear reactor irradiation facilities enables precise qualification of radiation effects to the irradiated samples such as nuclear heating or changes in their electrical or material properties. To support the increased utilization of the JSI TRIGA reactor irradiation facilities in the past few years mainly on account of testing novel detector designs, electronic components and material samples, we are working on increasing the neutron and gamma field characterization accuracy using various modeling and measurement techniques. In this paper we present the dose field measurements using thermo-luminescent detectors (TLD’s) with different sensitivities neutron and gamma sensitivities, along with multiple ionization and fission chamber. Experiment was performed in several steps from reactor start-up, steady operation and a rapid shutdown, during which the ionization and fission chamber signals were acquires continuously, while the TLD’s were being irradiated at different stages during reactor operation and after shutdown, to also capture response to delayed neutron and gamma field. The results presented in this paper serve for validation of JSI designed JSIR2S code for delayed radiation field determination, initial results of its application on the JSI TRIGA TLD measurements will also be presented.

EFFICIENCY OF PLANT IRRADIATION IN PROTECTED GROUND STRUCTURES

The advantage of LED lamps over conventional means of plant irradiation is described. An analytic expression is proposed to determine the relationship between LED lamp characteristics and plant parameters such as the stem growth and biomass. The formula also identifies the plant growth phase, which is crucial in development of automated energy-saving LED irradiation facilities for greenhouses.