A technician working for a firm dedicated to recycling used chemical packaging emptied the remainder of 2 small containers that had contained an aluminium chloride and iron-based flocculant (pH = 1) into a central vacuum tank. He then emptied this tank into a “clean” container slated for destruction, but this vessel still held some 13% sodium hypochlorite residue. The reaction between these 2 incompatible products triggered a gaseous emission. Stressed by the ensuing smoke and feeling the onset of suffocation, the technician removed his mask, which only increased his exposure to the vapours. Another employee also felt ill from this release. Fire-fighters and emergency medical services rescued the 2 employees suffering from pulmonary irritation. The inspection for classified facilities and the work inspection were duly informed.

Several causes were highlighted: no instructions provided when using a clean container to collect residue from the vacuum station, the safety data sheet for this aluminium chloride-based product not transmitted by the client and the hazard symbols on the product container failing to match those on the data sheet. Moreover, the technician had improperly placed his mask (having never been trained in equipment use) and the chemical risk training he received had been incomplete. The facility operator adopted the following measures:

• more extensive employee training in chemical risks;
• new training module for properly wearing individual protective gear;
• availability of individual respirators for the 2 technicians assigned to suction the used packaging;
• organisation of used packaging storage by chemical compatibility of the inherent hazards;
• package self-inspection procedure upon acceptance (check for match between safety data sheets and the waste acceptance certificate);
• procedure to follow for draining suctioned residue, with verification of the “clean” container.