Chapter 19
LIFTING PLANT AND OPERATIONS
Not covered in this document as they vary a lot and need special attention.
Chapter 20
WORK ON MACHINERY AND POWER SYSTEMS
Storage batteries: (Battery room) General
When a battery is being charged it ‘gases’, giving off both hydrogen and oxygen. As hydrogen is easily ignited in concentrations ranging from 4% to 75% in air, battery containers and compartments should be kept adequately ventilated to prevent an accumulation of dangerous gas.
Smoking and any type of open flame should be prohibited in a battery compartment. A conspicuous notice to this effect should be displayed at the entrance to the compartment.
Lighting fittings in battery compartments should be properly maintained at all times, with protective glasses in position and properly tightened. If cracked or broken glasses cannot be replaced immediately, the electric circuit should be isolated until replacements are obtained.
No unauthorized modifications or additions should be made to electrical equipment (including lighting fittings) in battery compartments.
Portable electric lamps and tools, and other portable power tools that might give rise to sparks, should not be used in battery compartments.
The battery compartment should not be used as a store for any materials or gear not associated.
A short circuit produces an arc or sparks that may cause an explosion. Do not overload circuits.
Insulation and/or guarding of cables in battery compartments should be maintained in good condition.
All battery connections should be kept clean and tight to avoid sparking and overheating. Temporary clip-on connections should never be used because they may work loose due to vibration and cause a spark or short circuit.
Metal tools, such as wrenches or spanners, should never be placed on top of batteries because they may cause sparks or short circuits. USE insulated tools only.
Jewellery, watches and rings, etc. should be removed when working on batteries. A short circuit through any of these items will heat it rapidly and may cause a severe skin burn. If rings cannot be removed, they should be heavily taped in insulating material.
The battery chargers and all circuits fed by the battery should be switched off when leads are being connected or disconnected. A lethal shock needs a current of only tens of milliamps and particular care should be exercised when the voltage exceeds 50V.
The battery-charging systems should be checked to ensure that it is only possible to charge within the specified rate.
Battery cell vent plugs should be screwed tight while connections are being made or broken.
The ventilation tubes of battery boxes should be examined regularly to ensure that they are free from obstruction.
Lids of battery boxes should be fastened while open for servicing and properly secured again when the work is finished.
Batteries should be kept battened into position to prevent shifting in rough weather.
Alkaline and lead-acid batteries should be kept in separate compartments or separated by screens.
Both acid and alkaline electrolytes are highly corrosive. Immediate remedial action should be taken to wash off any accidental splashes on the person or the equipment. Hands should always be washed as soon as the work is finished.
Batteries should always be transported in the upright position to avoid spillage of electrolyte
Storage batteries: lead acid
When the electrolyte is being prepared, the concentrated sulphuric acid should be added slowly to the water. If water is added to the acid, the heat generated may cause an explosion of steam, splattering acid over the person handling it.
Goggles, rubber gloves and a protective apron should be worn when acid is handled.
To neutralize acid on skin or clothes, copious quantities of clean fresh water should be used.
An eyewash bottle should be to hand in the compartment for immediate use on the eyes in case of accident
The corrosion products that form round the terminals of batteries are injurious to skin or eyes. They should be removed by brushing, away from the body. Terminals should be protected with petroleum jelly.
Storage batteries: alkaline
The general safety precautions with this type of battery are the same as for the lead acid batteries with the following exceptions.
The electrolyte in these batteries is alkaline but is similarly corrosive. It should not be allowed to come into contact with the skin or clothing, but in the case of an accident the affected parts should be washed with plenty of clean fresh water. Burns should be treated with boracic powder or a saturated solution of boracic powder. Eyes should be washed out thoroughly with water, followed immediately with a solution of boracic powder (at the rate of one teaspoonful to 1/2 litre or one pint of water). This solution should always be readily accessible when electrolyte is handled.
Unlike lead-acid batteries, metal cases of alkaline batteries remain live at all times and care should be taken not to touch them or allow metal tools to come into contact.
Chapter 21
HAZARDOUS SUBSTANCES AND MIXTURES
This is not covered under this heading. All unknown substances are considered as Hazardous and treated with cautions. Cleaning chemicals, Paints, Lubricants, and Hydraulic oils are considered Hazardous and covered elsewhere.