Worldwide, over 4 million babies die within a month of birth each year. Of these, 3.9 million are in developing countries. A proportion approximately 25% of these deaths are due to complications of premature birth, most commonly inadequate thermoregulation, water loss, and neonatal jaundice. An infant incubator provides stable temperature, relative humidity, and airflow values. A periodical calibration should be applied on infant incubator to monitor the functionality. The study aims to develop a calibration device that measures temperature, humidity, airflow, and noise in the baby incubator based on an Android application with Bluetooth communication to improve the calibration monitoring process. This is to achieve a better performance of the conventional INCU analyzer. The contribution of this research is that the values of the temperature, humidity, airflow, and noise can be displayed on both devices, the INCU analyzer machine, and mobile phone; thus, the user can monitor the measurement activities wirelessly. Furthermore, the statistical calculation for all measurements can be saved on a mobile phone device. The main design consists of temperature sensor LM35, humidity sensor DHT22, airflow sensor MPX5010DP, an analog signal conditioning circuit, an Arduino Mega microcontroller, Bluetooth module HC05, and Android mobile phone. The resulting design was compared to the standard or calibrator INCU analyzer machine (Fluke Biomedical INCU II). This study found that the smallest error is -1.72%°C, -0.106 % RH, -1.727% dB, and <0.1% m/s for temperature, humidity, noise, and airflow parameters, respectively. After the evaluation process, this device can be used as an INCU analyzer to calibrate the infant incubator.

X-ray radiation (ionization) cannot be felt directly by the five human senses. Therefore, radiation monitoring is needed, one of which by using a survey meter. The purpose of this research is to directly monitor the level of radiation exposure and leakage of X-ray tube containers in the work area. This was done to ensure the safety and health of workers in the radiation transmission area, so that it is in accordance with the ALARA (As Low As Reasonably Achievable) principle, which is stipulated in the Decree of the Minister of Health RI No. 1250/Menkes/SK/XII/2009 concerning Guidelines for Quality Control of Radiodiagnostic Equipment as Standard Values ​​for X-Ray Radiation Monitoring. This research is an experimental study with a survey meter equipment module design using a Geiger Muller sensor equipped with data storage. This module design method uses Arduino programming as data processing and is displayed on the CHARACTER LCD. Test analysis was carried out by comparing the measurement value of the module with the standard value as a standard for comparison. Based on the measurement results, the X-ray tube leak test value resulted in a standard AAT survey meter value of 0.001 both using a closed and unsupplied 2mm Pb circuit, namely 0.00097 mGy/hour and 0.00092 mGy/hour. Meanwhile, the results of the tube leakage test using a survey meter, both circuits, modules, and standard survey meters show a passing grade test value of < 1mGy/hour. In conclusion, the module design using the Geiger Muller sensor is feasible to use.