There are strict guidelines covering those who work in dangerous environments, in particular those who have to enter into confined or restricted spaces. There's some confusion, however, when it comes to the definition of "confined" versus "restricted." What's the difference?
Fundamentally, a confined space is an area that is not intended or designed to be occupied by a person and could cause a risk due to oxygen levels, the presence of contaminants or engulfment.
A restricted space, conversely, is an area that does not have the aforementioned risks but does have physical restrictions that may impact the activities that can be carried out there.
There are different procedures in place for those who manage facilities, and these vary according to whether the space is defined as confined or restricted.
Conditions Relevant to Both
In both cases these areas have to be properly identified and entered into a register that is maintained at the facility by management. All of these locations must further be identified by proper signage, and the entry points to the spaces have to be kept under lock and key. The facility has to conduct a full risk assessment in writing before any work can be conducted in a confined or restricted space. This will identify the nature of the hazards that could be faced, how the work is to be undertaken, the level of risk expected and what response would be made in the event of an emergency.
In all cases it's necessary to have a carefully planned and rehearsed emergency response procedure, ready to be implemented at a moment's notice. Also, all those employees who may as part of their description be required to enter either a confined or restricted space must undergo full training so that they are familiar with all the elements. They must be familiar with the definitions, the types of hazard that they could encounter, how to assess and control risks and what will happen in the event of an emergency. Each of these employees must be reassessed on an annual basis before they are allowed to work in confined or restricted spaces in the future.
Conditions Specific to Confined Spaces
In the case of confined spaces in particular, written authority has to be issued by the person who is in control of the area before anybody can enter or any work commence. This written authority cannot be issued until the aforementioned risk assessment has been completed.
Also, these confined spaces must have the atmosphere tested and monitored to ensure safe oxygen levels and manageable contaminant risk. If atmospheric levels are found to be raised, then nobody will be allowed to enter the confined space area without respiratory devices.