## 1 Introduction  
Multigap Resistive Plate Chamber (MRPC) technology has been widely used in high energy physics experiments for high precision Time-of-flight (TOF) measurements since its development in 1996 [1]. The time resolution, including the detector and the readout electronics, commonly reaches less than 100 ps, such as 60 ps at RHIC-STAR and 56 ps at LHC-ALICE [2, 3, 4]. For future experiments, the interaction rate by collision is designed to increase by orders of magnitude in order to reach specific states of nuclear matter or to detect rare probes which feature an extremely low yield. Thus, rate capability becomes a new challenge to the application of MRPC. There are two main challenges we must solve: the rate capability of the detector, and timely gas exchange in the gaps. Based on the Ohmic Model [5], one can decrease the bulk resistivity of the resistive plates to improve an MRPC's rate capability. Thus, new materials such as low-resistive glass [6] and ceramic [7] have been developed. Alternatively, the proposal of warming the detector has been discussed [8]. Thanks to these successful studies, the rate capability of the MRPC, tested in-beam, expands from the original level of 1 kHz/cm\({}^{2}\) to a stunning 100 kHz/cm\({}^{2}\) level [9], making it possible to be applied to those experiments with unprecedented luminosity, such as FAIR-CBM [10] and JLab-SoLID [11].  
However, due to the restriction of the current beam test setup, the experimental level of wide and long-term exposure under high luminosity cannot be realized smoothly. Either the smaller size of irradiation limited within the beam profile (e.g., the 3.5 cm diameter beam spot in [9]), or the less avalanche charge in the gas gaps caused by the shorter irradiation time, leads to the under-estimation of the pollutant production in MRPC's operation. In successive flux, it is expected that more working gas molecules will be ionized in the 100 \(\upmu\)m level gas gaps. However, the quantity of the ionized products, their diffusion conditions, and the potential risks for detectors at high rate, still need detailed investigation. In Section 2, some simulation results and experimental observations are reviewed concerning gas pollution at high rate. Although a consistent and quantitative conclusion cannot be obtained from these works carried out at different times, we can still find the potential link between the risks in MRPC operation and gas pollution. Further, it can be inferred that a smaller gas volume will promote the gas exchange and pollutant discharge from the gas gaps.  
A newly developed sealed MRPC is aimed at an extremely low gas volume. In the context, \"sealed\" refers to the mostly enclosed lateral side of the MRPC with only inlets placed, so that the working gas can be directly streamed into the MRPC gas gaps. With the development and test of the sealed MRPC [12], especially the long-term test with extremely low gas flow, it is further believed that the exchange rate of the working gas will be accelerated thanks to the much lower gas volume. However, the proposed application of this type at first is in low flux experiments, and the focused benefit is to reduce the working gas consumption. The findings in Section 2 have given a new perspective to the sealed design. A high-rate sealed MRPC, featured with low gas volume and equipped with the low-resistive glass instead to enhance the rate capability, is proposed to solve the gas pollution effect. Thus, the development and test of the high-rate sealed MRPC can properly validate the link between the negative detector behavior and the gas pollution.  
Based on the motivation, a high-rate sealed MRPC prototype has been produced and tested in cosmic rays to verify the performance. Afterwards, the current behavior of the prototype in X-rays has been examined. In Section 3, the results are shown and the current behaviors of the sealed type are compared with that of the common MRPCs described in Section 2.