This work presents field test results of silane releases from a cylinder valve into an open environment and into a gas cabinet. The following release tests were performed: (1) Leak from the valve outlet connector with and without a restrict flow orifice (RFO), (2) Leak directly from the two leak check holes of a capped Diameter Index Safety System (DISS) after the cylinder valve with and without a RFO, (3) Leak from cylinder valve stem retainer thread (via the loosened valve), and (4) High pressure releases from a 0.32-and 0.64-cm tube into a ventilated single cylinder gas cabinet.Release pressures varied from 120 psig to the full cylinder pressure of 1,250 psig. Both digital video and high speed cameras were used to record the ignition, pop, and explosion behavior. The results confirmed that the ignition behavior of a silane leak is strongly related to the release pressure, flow rate, aperture, and the exit environment.This study has shown that silane leaks from a fully opened cylinder valve (without an RFO) or the loosened retainer thread will not autoignite while a silane leak from fully opened cylinder valve (with an RFO) or a loosened DISS cap with and without an RFO will ignite immediately even at full cylinder source pressures.The RFO results show that the RFO increases the likelihood of the autoignition of the release, and significantly decreases release rate and the intensity of the flame. This information is important when designing systems and developing safe practices for handling silane cylinders in the semiconductor and thin-film transistor liquid crystal display (TFT-LCD) industries. The results also demonstrates safe cabinet ventilation rate to prevent explosions.

In this work, the shock sensitivity of hexachlorodisilane (HCDS) hydrolysis products was studied. The hydrolysis conditions included vapor and liquid HCDS hydrolysis in moist air. Shock sensitivity was determined by using a Fall hammer apparatus. Extensive infrared studies were done for the hydrolysis products. It was found that the Si–Si bond in HCDS during hydrolysis is preserved and can be cleaved by shock, leading to intramolecular oxidation of the neighboring silanol (Si–OH) groups to form a networked Si–O–Si structure and hydrogen gas. The limiting impact energy for shock sensitivity was also found proportional to the oxygen/silicon ratio in the deposit. Finally, recommendations are given for controlling the shock sensitivity of the hydrolyzed deposit.

Academic institutions are faced with the complex problem of accurately determining the hazards associated with a proposed or ongoing project. For many reasons, compressed gas safety can be a significant challenge at universities, especially those that involve research using many uncommon materials. This article is a call to action for implementing better safety practices when using compressed gases and helps to fill the gap on resources related to compressed gases. General operating procedures and resources for safe practices when using compressed gases are outlined in this article, as well as lessons learned from incidents involving compressed gases.

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