What are confined space signs?
Confined space signs simply warn people that an area is considered a confined space. A Confined spaces is large enough for a person to enter, but have restricted means of exit. This might be a tank, a tunnel, a sewer or some other industrial space. There is usually only one restrictive (smaller than a doorway) way in or out, and it is not designed for continuous occupancy. Lack of adequate ventilation also plays a factor.
Why are they necessary?
Confined spaces are more dangerous than other places. Individuals in these locations are at a greater risk for poisonous gas exposure, entrapment, and other industrial injuries. Warning signs are the first line of defense against accidents, injuries or worse.
Sometimes the law also comes into play. OSHA, the US federal government's occupational safety agency, requires certain confined spaces to have warnings posted. Workers wanting to enter these spaces must have entrance permits. These locations, called permit-required confined spaces, are deemed to have potentially serious hazards. Workers in these environments must receive safety training because of the elevated danger.
Varieties
Confined space signs serve two basic roles: they either alert people of a danger (alert signs or they're posted to help authorize entry (authorization signs).
Alert signs come in many forms. There are basic plastic signs with adhesive backings and more durable sticky vinyl signs. Both styles are convenient and inexpensive, but can only be used once. Other signs can be mounted with screws or built-in magnets, design features that allow them to be used indefinitely.
Authorization signs are even more varied. Certain barrier-type models physically restrict entry by blocking openings, while others contain holders to insert permits. Permit authorization signs also come in the same basic plastic models as alert signs.
Each confined space contains unique dangers, which in combination with applicable laws, will dictate the type of signage your site will need. Of course, it's important to think beyond legal requirements; these relatively inexpensive signs can save lives. That is why they're some of the most important items you can buy for your work site.