A confined space is big enough to enter, has limited means of entering or exiting, and is not intended for regular human occupancy. Confined spaces can include manholes, electrical vaults, tanks, boilers, silos, storage bins, hoppers, water trucks, vacuum trucks, under pier work, ship holds and barges. Trenches may even be confined spaces if they contain a hazardous atmosphere.
Confined spaces can have very hazardous atmospheres. These include low or high oxygen levels, hydrogen sulfide (sewer gas), carbon monoxide from vehicle exhaust or torch cutting, or flammable gases like methane. Your air monitor measures for all of these things. The alarm on the monitor happens in 3 ways. There is an audible alarm, a loud beeping sound. The monitor will also flash. Our monitors also vibrate to warn workers who are wearing the monitor. You must test every single type of confined space, and the ones with gas readings require a monitor to be testing the air 100% of the time.
Other hazards in confined spaces include engulfment hazards from water or small solids, electrical lines, mechanical equipment that can trap workers, hydraulic, pneumatic and steam.
Requirements for entering a confined space start with a Competent Person. This person is trained, and designated by the employer. A competent person must assess the confined space each day before anyone enters, and they ensure it is safe to enter. There are three types of confined spaces entries. The competent person will designate a space as one of the following:
Non-permit – this space is safe to enter without special equipment, but the space will still be tested twice a day with the air monitor.
Permit – this space is not safe, due to an unsafe atmosphere, and other possible hazards. This requires continuous ventilation, continuous air monitoring and other controls to ensure safety. This entry requires an attendant, an entrant and a supervisor, in addition to logging down whenever someone enters or leaves the space.
Alternate entry – this space may have a hazardous atmosphere, but it is controlled by ventilation, and no other hazards exist. Continuous air monitoring and ventilation is required for this type of entry.
As a worker who may enter a confined space, you have the right to see the air monitoring being performed. If an air monitor alarm goes off while you are in a confined space, you must leave the space until the atmosphere is confirmed to be safe and the safety department has been notified and approves workers reentering the space. The air monitor must be bump checked every day, and calibrated every month. Do not use equipment that needs servicing.
No matter which type of confined space we work in, we cannot enter a space to rescue someone. Our entries are set up so that a worker can rescue another person using a retrieval system while remaining outside the confined space. This system involves a tripod, a winch, and a fall harness. This allows the person up top to winch up a worker from a confined space without exposing themselves to the hazards. Blowers must always be available to provide fresh air to someone in a confined space. It can reduce contaminants in the confined space, and also provides cooling for the worker inside. Do not allow a worker to unclip from the rescue device.
By choosing the best equipment, providing training and setting up procedures to identify and correct hazards, we can reduce the risks encountered in confined spaces. Your contribution includes: attending training, using equipment properly, being aware of hazards and reporting them, working safely and looking out for your coworkers. Make sure you inspect your gear for damage and report deficiencies. It is the only thing between you and a disabling or fatal injury.