An Effective Mitigation for Phosphine Present in Ammunition Container Assemblies and in Munitions Containing Red Phosphorus

Abstract

A major issue associated with munitions containing red phosphorus is that, during storage, red phosphorus can react, in the presence of moisture and air, to form a mixture of corrosive phosphorus acids and the toxic gas phosphine. This has raised serious concerns relating to the health and safety of personnel handling these munitions. This paper details the studies undertaken to assess the suitability of a chemically impregnated activated carbon cloth (phosphine getter material – PGM) for the static adsorption of phosphine evolved from munitions containing red phosphorus and its effective mitigation of phosphine present in both ammunition container assemblies and within the main body of munitions of this type. Laboratory assessment of PGM was undertaken along with real‐life ammunition container assembly trials covering several munitions containing red phosphorus and accelerated ageing trials using modified countermeasure cartridges. Reaction products formed from the reaction of phosphine with chemical impregnates were studied using scanning electron microscopy (SEM) and energy dispersive X‐ray analysis (EDX). Aqueous extraction of the phosphine reacted PGM confirmed the presence of the acidic species orthophosphoric acid (H3PO4) and phosphorus acid (H3PO3).

Safer Pyrotechnic Obscurants Based on Phosphorus(V) Nitride

“…PH 3 and phosphoric acids severely affect the chemical stability of pyrotechnic formulations and compromise the safety of the munitions based thereon and the workers handling them. Pyrotechnic manufacturers have therefore been integrating absorbing pads based on active carbon into payload containers and have been designing PH 3 ‐venting mechanisms for payload casings …”

Phosphor(V)‐nitrid macht pyrotechnische Tarnnebel sicherer

“…PH 3 und die Säuren beeinflussen die chemische Stabilität pyrotechnischer Sätze und gefährden die Sicherheit der mit diesen Sätzen hergestellten Munitionen sowie die damit beschäftigten Personen. Die Hersteller pyrotechnischer Munition integrieren daher Adsorber auf Aktivkohlebasis in die Wirkladungsbehälter und versehen diese auch mit Entlüftungsmechanismen für PH 3 …”

Preparation, Characterisation and Performance of Microencapsulated Red Phosphorus

“…The main military applications for phosphorus and its compounds are igniters, incendiaries, screening smoke ammunition, flame, smoke signals and decoys [1][2][3]. However, RP-based smoke compositions slowly degrade in the presence of air and trace moisture, producing acids that can corrode munition components and phosphine gas that is highly toxic and flammable [4,5]. Additionally, RP-based smoke compositions are generally very sensitive to unintended ignition by friction [6].…”