Do not overlook potential hazards of carbon monoxide (CO) that may exist on the jobsite. It is an especially dangerous hazard because it is odorless, colorless, and tasteless. CO attacks red blood cells when it enters into the system. Therefore, it attacks the ability to absorb and distribute oxygen to the body. Symptoms of CO exposure are a dull headache, dizziness, weakness, nausea, vomiting, shortness of breath, confusion, blurred vision, and loss of consciousness. If anyone on the jobsite is feeling these symptoms, look for sources of CO and immediately take the person into a fresh air environment. If CO poisoning is not treated, it can cause permanent brain damage, damage to the heart, and death.

Before work commences, check levels of CO. Be aware of where gas-powered equipment will be used and monitor levels in those areas. Especially when working in an enclosed area, CO levels should be monitored closely. While work is being done, have a detection system in place that will give warning when CO is present at levels that would be harmful to employees.  

Motor Vehicles
Motor vehicles are a common source of CO. Do not leave vehicles running in areas where employees are working at levels lower than the vehicle. For example, do not leave a vehicle running near a trench where a worker may be present as the car exhaust will enter the trench and cause the levels of CO and carbon dioxide to increase.    

Gas-Powered Tools
Gas-powered tools can give off CO as they are being used. Ensure there is proper ventilation available. Where possible, open the work space to allow for greater ventilation. During winter months, make sure there are proper-sized cutouts in coverings to allow sufficient ventilation. When working inside an enclosed part of a structure, find a means of ventilation. If needed, provide forced air to better circulate the area. 

Power Generators
When gas-powered generators are being used, place them in an open, well-ventilated area. When placed close to the building, exhaust from generators can seep into the structure.

Fuel-Burning Heaters
Heaters are common in the winter on jobsites. Ensure that exhaust ventilation is provided to avoid a buildup of CO in a work area. Ensure that employees have been properly trained on the use of heaters that can operate on either propane or natural gas. Each type of gas requires a different pressure and CO can build up if the correct pressure is not selected. Lock valve in place after gas is selected to avoid problems.  

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NOTICE: This guide may make reference to the Occupational Safety and Health Administration (OSHA) regulations; however the guide is not legal advice as to compliance with OSHA or other safety laws, codes, or regulations. Compliance with OSHA and other safety laws codes or regulations, and maintaining a safe work environment for your employees remains your responsibility. WCF Insurance does not undertake to perform the duty of any person to provide for the health or safety of your employees. WCF Insurance does not warrant that your workplace is safe or healthful, or that it complies with any laws, regulations, codes, or standards.