Portable Generators and Engine Driven Machinery Dangers
Portable generators are useful when temporary or remote electric power is needed, but they also can be hazardous. The primary hazards to avoid when using a generator are carbon monoxide (CO) poisoning from the toxic engine exhaust (from petrol engines), electric shock or electrocution, and fire.
Every year, people die in incidents related to portable generator use. Most of the incidents associated with portable generators, involve CO poisoning from generators used indoors or in partially-enclosed spaces.
Carbon Monoxide Hazards
NEVER use a generator or petrol engine machine in enclosed or partially-enclosed spaces. Generators can produce high levels of CO very quickly. When you use a portable generator, remember that you cannot smell or see CO. Even if you can’t smell exhaust fumes, you may still be exposed to CO.
If you start to feel sick, dizzy, or weak while using a generator, get to fresh air RIGHT AWAY. DO NOT DELAY. The CO from generators can rapidly lead to full incapacitation and death.
If you experience serious symptoms, get medical attention immediately. Inform medical staff that CO poisoning is suspected. If you experienced symptoms while indoors, have someone call the fire brigade to determine when it is safe to re-enter the building.
Follow these safety tips to protect against CO poisoning:
NEVER use a generator indoors, including in homes, garages, cellars, garden sheds, boats, tents, cabins and other enclosed or partially-enclosed areas, even with ventilation. Opening doors and windows or using fans will not prevent CO build-up in the home.
Follow the instructions that come with your generator. Locate the unit outdoors and away from doors, windows, and vents that could allow CO to come indoors.
Install battery-operated CO alarms or plug-in CO alarms with battery back-up in your home, motorhome, boat or any area you are occupying that may come into contact with exhaust fumes, according to the manufacturer's installation instructions. The CO alarms should be certified to the requirements of the latest safety standards for CO alarms.
Test your CO alarms frequently and replace flat batteries.
Do not use a portable generator in an enclosed area. NEVER USE exhaust extensions as this will cause additional strain on the existing exhaust system and cause it to fail, allowing poisonous carbon monoxide to enter the living area.
LPG Converted Generators
All LPG converted generators should have the installation approved by a Gas Safe registered engineer - www.gassaferegister.co.uk
Exceptions to this regulation are when used in the following applications, however we would recommend it is still inspected by a qualified engineer.
1. A caravan used for touring otherwise than when hired out in the course of a business
2. A sea-going vessel
3. A vessel not requiring a national load line certificate except when such a vessel is-
- (i) Hired out in the course of a business
- (ii) Made available to members of the public in the course of a business carried out from that vessel; or
- (iii) Used primarily for domestic or residential purposes.
We would recommend that all installations are checked and approved by a Gas Safe approved engineer.
Follow these tips to protect against shock and electrocution:
Keep the generator dry and do not use in rain or wet conditions. To protect from moisture, operate it on a dry surface under an open, canopy-like structure. Dry your hands if wet before touching the generator.
Plug appliances directly into the generator. Or, use a heavy duty, outdoor-rated extension cord that is rated (in watts or amps) at least equal to the sum of the connected appliance loads. Check that the entire cord is free of cuts or tears and that the plug has all three prongs, especially a grounding pin.
NEVER try to power the house wiring by plugging the generator into a wall outlet, a practice known as back feeding. This is an extremely dangerous practice that presents an electrocution risk to utility workers and neighbours served by the same utility transformer, also there is the real risk of someone unknowingly removing the plug, which would be live and the possible fatal consequences. It also bypasses some of the built-in household circuit protection devices.
If you connect the generator to the house wiring to power appliances, you MUST have a qualified electrician install the appropriate equipment in accordance with local electrical codes. Or, check with your utility company to see if it can install an appropriate power transfer switch.
For power cuts, permanently installed stationary generators are better suited for providing backup power to the home. Even a properly connected portable generator can become overloaded. This may result in overheating or stressing the generator components, possibly leading to a generator failure, so care must be taken to use your household appliances in such a way, so as not to overload the generator.
Fire and Explosion Hazards
Follow these tips to prevent fires:
Never store fuel for your generator in the home. Petrol, diesel, and other flammable liquids should be stored outside of living areas in properly-labelled, non-glass safety containers. Do not store them near a fuel-burning appliance, such as a natural gas water heater in a garage. If the fuel is spilled or the container is not sealed properly, invisible vapours from the fuel can travel along the ground and can be ignited by the appliance pilot light or by arcs from electric switches in the appliance.
Before refuelling the generator, turn it off and let it cool down. Petrol spilled on hot engine parts could ignite.
It is not recommended to use a petrol or LPG generator on a boat - If there is a leak or spillage, the petrol vapour given off from the petrol or LPG gas will accumulate at the bottom of the boat hull, Petrol vapour and LPG gas are heavier than air. The slightest spark (even turning on a light switch) could ignite this vapour and cause an instant explosion.
Never use a portable generator in a moving vehicle.
Connecting a Generator to Your House
We would only recommend connecting a 5kw (or larger) size generator to you premises.
When using a generator as an alternative supply to the mains, there are several precautions that must be observed.
It is vital that the generator is completely isolated from the mains supply. This ensures that the generator is not attempting to power up the whole neighbourhood, but also ensures that it does not electrocute a utility worker trying to restore the mains supply.
To achieve this, a double-pole, break-before-make, changeover switch must be installed by a qualified electrician.
The HD manual changeover switch should be used for this application. This should be fitted between the electricity meter and the building consumer unit. The switch connects the building to either the mains supply or to a lead, which can be plugged into the generator. Most buildings now have an RCD built into the consumer unit. This is configured to operate from the mains supply with an earthed neutral, and not from a generator with a floating earth. To utilize this protection device, it is necessary to modify the generator so that it is configured in the same way as the mains supply.
This is a simple modification for a qualified electrician, involving adding a link wire from the neutral terminal to the earth terminal. It is recommended to make this connection in the plug that is to be used to connect to the generator. This ensures that the generator is unmodified when it is disconnected from the house, and therefore remains safe.
The plug should be labelled: ‘Do not connect to mains: Neutral-Earth link fitted’
The lead between the generator and the transfer switch is not protected by the RCD, it is therefore recommended to use a steel armoured cable for this connection. Finally a local low-impedance earth spike needs to be installed.
All generators we supply are equipped with a breaker switch or overload protection, this will trip out in the event of a direct short or heavily overloaded, however, it may not trip out if the generator is very slightly overloaded. Care must be taken, not to overload the generator, as serious damage will be caused to the generator.
It is vital that a qualified electrician installs your changeover switch and that it has the correct rating for your application, and installs your changeover switch.