A confined space is a working location with limited means of exit or entry. Often, these spaces allow only limited movement and may have poor ventilation. Management of activity in confined spaces is an important topic in workplace safety, as workers may be exposed to increased risk due to the limitation in size.
There are many different types of location that may be considered a confined space. Some of the more common varieties include pipelines, sewers, storage tanks, and manholes. They are often used for the storage of equipment or the containment of gas or liquid material. Ships, infrastructure systems, and industrial factories are places where confined spaces may be common. Generally any space that allows only limited movement may be considered a confined space for safety purposes.
Many union and safety organizations have strict workplace safety guidelines when it comes to confined spaces. These safety requirements try to ensure a consistent process of risk assessment, proper training and behavior in a confined space, and contingency or rescue plans in case of accident. Some safety organizations, such as the US-based Occupational Safety and Health Administrations (OSHA), require that certain confined spaces undergo a permitting process in order to remain in compliance with legal standards.
There are several workplace safety issues that may be important when considering confined space use. First, the limited amount of movement and often narrow entry and exit passageways may lead to an increased risk of becoming stuck or trapped. Falling can be a major concern, as some of the confined spaces are precariously high even if narrow. One of the most common problems is inadequate temperature control and ventilation, which can lead to the inhalation of dangerous substances, asphyxiation, or heat and cold stress.
There are usually several means by which operations in a confined space can be made safer for workers. First, the employer must ensure that the process meets all legal requirements, in order to know what risks exist and how to combat increased danger. Second, employees that are allowed into confined areas must be well trained in safety and emergency methods, and be free from problems such as claustrophobia or asthma. Appropriate and pre-examined safety equipment must be provided, such as masks, safety wires, and ventilation systems.
Since an open confined space is a danger to those in the vicinity, it is also important to post signs and behavioral guidelines when a space is being used. Signs may explain the nature of the risks, such as hazardous gases. It is also important to carefully mark and place signs around any open container or space that could be a cause of falls. Protecting the people around the area can also help protect the workers inside a confined space.