Sigma-HSE News

From our Experts: Case Study – Asphyxia Hazard

Permit to work procedures and adequate risk assessments in confined spaces:

A grain store processing/handling area was below ground and identified as a ‘confined space’ although physical access was not barred other than by a warning. The risk to staff comes from the potential for wet grain to decompose releasing carbon dioxide and subsequent risk of asphyxiation.

The recommendation is for a physical barrier, with key entry, to be used to prevent access without a written permit, issued with the relevant key and a gas monitor to be issued, and used, as a mandatory requirement rather than on request.

The risk from asphyxia is equally valid for other industries such as Pharmaceutical and Chemical, where they may use inerting or partial inerting as their ‘basis of safety’.