This invention is a magic-angle-spinning (MAS) nuclear magnetic resonance (NMR) probe with a unique sealed and filtered sample compartment. The modular two-layer compartment was conceived to ensure secure, efficient containment of hazardous samples while preserving convenience of operation and state-of-the-art NMR performance. High resolution NMR experiments on solid samples typically require the flow of large volumes of gas at high pressures (>50 psi) to spin rotors containing the sample. Under conditions of high gas flow, dispersal of a hazardous sample can occur through leaks or failure of the rotor. The containment system described here allows high pressure gas to flow into the compartment to spin the sample, while providing a securely filtered exit port to vent the gas. Even in the event of a failure of the rotor, such a compartment will prevent the dispersal of sample outside the containment area. The modular design allows the sample compartment to be separated from the rest of the probe for convenient cleanup, disposal, or contamination checks. In addition to its protective function, the sealed compartment can also be used to maintain a sample in an inert atmosphere during MAS NMR experiments. This is in contrast to standard MAS NMR probes, which are usually well ventilated and open to the atmosphere in order to allow the free flow of gases.