Ventilation Confined Space Entry Operation,

 

Ventilation is the best method for making a confined space atmosphere safe and free of hazardous air. Planning the confined space entry operation, and selecting the proper ventilation equipment is critical. It is almost an art form to ensure every nook and cranny of the confined space is continuously ventilated. It also takes a little math to figure out how long it takes to ventilate a certain sized confined space with the equipment you have.

Types of ventilation
Some confined spaces can be ventilated naturally. This is the case with most excavations. However, any time a naturally ventilated confined space is occupied, adequate precautions must be taken to prevent employee exposure to air containing less than 19.5 percent oxygen and other hazardous atmospheres.

Other confined spaces must be ventilated with mechanical equipment.

Ventilation is important to:
• Clear the confined space of hazardous air before you are permitted to enter.
• Keep the confined space clear of hazardous air while you are working in the space.
• Keep the confined space comfortable by lowering temperatures and providing fresh air.

Types of equipment
Blowers provide a continuous supply of outside air. Ventilation blowers can work two ways. They can either force fresh air into the confined space or suck the contaminated air out and pull fresh air in. The most popular (and efficient) method of the two is forced air.

Ducting is also important. The positioning can mean proper circulation and venting of the whole confined space or leaving pockets of contaminated air in corners.

If you are using blower equipment in a potentially explosive hazardous atmosphere you must use equipment designed to be spark-proof and have the ability to dissipate static electricity.

Because of the complications of selecting the right equipment, your site’s competent person must know how to evaluate the confined space and select equipment powerful enough to exchange air in the space. The size and configuration of the space and the output of the blower must be evaluated.

Confined space work can be safe. Proper and continuous ventilation is one of the best and easier methods to accomplish a hazard free confined space.