Explosion protection document for two large municipal wastewater treatment plants.

2023 / Advice on health and safety in the workplace / Infrastructures

For the plants under study, which are among the largest in Italy, the probability of the formation of an explosive atmosphere and the presence of ignition sources cannot be disregarded, and the explosion risk was assessed.
The wastewater treatment process necessitated a dual assessment to take into account the possible explosive atmosphere generated by both flammable gases (biogas from bacterial fermentation, methane used by industrial boilers, diathermic oil used as a heat transfer fluid, hydrogen developed when recharging electric motor vehicles) and combustible dust (dried sludge).
The study was conducted on the basis of the conclusions of the classification of areas at risk of explosion due to the presence of flammable gases and combustible dusts.
The assessment of the explosion risk was carried out in accordance with Title XI, Article 294 of Legislative Decree 81/08 and subsequent amendments and additions, following the methodology suggested by INAIL.