Even seemingly benign materials can be hazardous when they escape their containers. Sugar spills at the Imperial Sugar plant near Savannah, Georgia in the US contributed to a chain of explosions in 2008 that killed 14 workers and caused millions of dollars worth of damage. Something as innocuous as milk, in enough volume, will kill fish in a watercourse or promote algal growth in drains.
What can go wrong
Safety hazards If the spilled material is flammable, as in the case of paint, solvents, diesel fuel, heating oil, petroleum-based oils or gels and machine oils, it can generate flammable vapours, depending on the location, ambient conditions and the presence of ignition sources. The spill of a flammable product in a confined workshop or store room, left unattended and then presented with an ignition source can result in a serious fire or explosion.
The most common sources of ignition in a workplace are naked flames, including welding and cutting equipment, smoking, electrical lighting, heating, motors and power circuits that are not flameproof, hot surfaces such as fan heaters and radiators, processes and vehicles (such as forklift trucks) that involve friction or sparking, static electricity -- caused by material movements including dry powders and free-falling flammable liquid -- chemical reactions and direct sunlight.
In poorly-ventilated areas, a spill may lead to a collapse, especially in a low-lying or confined space if the material is flammable. There are recorded cases of worker fatalities in agricultural slurry pits where people have been overcome with asphyxiants that are heavier than air, such as carbon dioxide. Online asphyxiation calculators can help predict oxygen availability in the event of a release of an asphyxiant, which can aid decisions on when to send a rescuer into a confined spill area (www.klausbruckner.com/asphyxiation.html).
Health hazards These could manifest in the form of harm to skin, eyes and the respiratory system. In extreme cases there is a risk of internal organ damage.
The spill will be liquid, powder or gas. Breathing in fine dust or vapour from powder or liquid spills can cause short- or long-term ill health. The chemicals may enter the lungs but can then affect the kidney, liver or heart. The effects are more pronounced in enclosed spaces with poor ventilation. Vapour may lead to narcotic effects, sleepiness or even unconsciousness.
Many chemicals can penetrate even unbroken skin, causing ill effects in other parts of the body.
Environmental hazards Spills may have serious consequences on the natural environment near the workplace. Liquids can soak through the ground to reach ground water, or can run into ditches and watercourses. Spilled materials can travel far in running water before they are detected and dealt with, causing severe damage to wildlife. One litre of diesel can pollute one million litres of water.
It is important to know where your site drains lead to. There are two main types: surface water to take away the rainfall and foul sewers that take the domestic waste to treatment works. However, in remote places of work and in farms, there may be only soakaways or ditches that may lead to the nearest public waters or ground water.
All spills must be cleaned up as soon as practicable in the safest manner possible without putting the responders in danger.
The first steps that you take are the most critical for a safe outcome and should be proportionate to the incident's nature and scale. The magnitude of risk will depend on these metrics and the hazards the spill presents to those who are exposed.
The main hazards fall into four broad categories: slips and falls, health exposure, explosion and fire, and environmental pollution.
As soon as you are informed of an incident, all personnel who do not need to be at the scene must be cleared from the affected area immediately and an alarm raised if the spill is known to be hazardous.
If the substance is hazardous you should simultaneously find out whether anyone has come into contact with it and arrange first aid if necessary and follow-up medical attention. In the case of hazardous powder, such as cement or strong detergent, first aiders can wash off the contamination.
If the substance is unknown, it is prudent to treat it as hazardous until proven otherwise. Depending on the area, access can be restricted by closing doors if it is inside, and placing barrier tapes, traffic cones and warning notices. If the risk is severe enough, these may need to be bolstered by sentries posted on access routes a safe distance from an exclusion zone for explosion, fire or fumes.
The next step should be to prevent further spills if there is any safe means of doing so. Discourage acts of heroism; people should not go into an exclusion area if it puts them or their colleagues in danger.
Next, gather information from the person who reported the spill and those who know the area and materials. The details you need include:
its state (flowing or stable)
the location. Is it enclosed or open? Are there any materials nearby that could compound the hazard? Are there any drains that it could enter?
If the liquid spill is non-hazardous, you have to determine whether it poses a slip risk. I have investigated a head injury that had arisen from the spill of an inert powder additive that was translucent -- so difficult to see on the floor -- and extremely slippery. A spill that was neither reported nor cleaned up led to a slip and fall in the next shift when an employee fell onto a vertical steel column and sustained a head injury.
Who does what
To make an efficient and effective spill response, you must allocate emergency arrangements in advance and allocate roles and responsibilities, coupled with training and periodic refreshers. These could be tabletop exercises with a simple opening statement: we have a spill -- what are the immediate steps we must take? Or you could stage a mock spill. This would test communications as well as clean-up procedures. If the people take ownership of spill procedures and clean-up, half the battle is won.
The US Chemical Safety Board offers several animated re-enactments of spill-related accidents (bit.ly/2cBPkae). The Health and Safety Executive in the UK provides useful guidance on safe handling of flammable liquids in containers (bit.ly/2cALddx) and powders (bit.ly/2cJwomj).
It is a legal duty in the UK--- and good business practice everywhere -- to involve safety representatives in your spill response plans and training. People on the shop floor have tremendous knowledge and practical skills that are best used in a co-operative and constructive manner.
It is prudent to build up a readily available inventory of all spillable substances on your premises. This is especially recommended for everyday use items such as paints, thinners, detergents, machine oils, cement powder, cleaning fluids and powders.
For materials stored in large quantities that could pose more serious hazards, suppliers should be able to provide much of the information you need to prepare a spill response plan. If the material that could be spilled is categorised as hazardous under the Classification, Labelling and Packaging Regulations or dangerous for transport under the European regulations concerning the international transport of dangerous goods by road (Accord Dangereux Routier), the supplier is legally required to provide you with a compliant safety data sheet (SDS). The most important sections in an SDS when dealing with hazardous spills are listed in the diagram opposite. These sections explain the actions to take to prevent exposure. In the UK, for substances in the scope of Control of Substances Hazardous to Health (COSHH) Regulations, this information should be included in COSHH assessments.
One litre of diesel can pollute one million litres of water
There are many types of spill response equipment, but a typical spill kit will include a mobile bin with a lid containing oil- or chemical-absorbent pads, inert absorbent such as granules and plastic bin bags to store the spill.
One way to decide how to stock a spill kit is to carry out a spill risk assessment based on answers to the following questions:
How much would I spill in a worst-case scenario?
Who would be expected to clean it?
How would they go about it?
What is the potential pollution linkage, including source, pathway and receptor, for the spill?
What do I need to deal with the spill? For example mop, bucket, dust pan, vacuum cleaner, personal protective equipment, barrier tapes, warning signs, SDS availability/disposal containers.
Could the spill involve special considerations such as confined space working, or a need for breathing apparatus?
Where will a spill kit be most easily accessible?
How will I maintain the kit?
What training should I give to employees to use the kit in an effective and safe manner?
Does my spill response procedure specify the location of the spill kit and how to replenish it?
In some cases, spills may become reportable to the authorities under regulations such as the Reporting of Injuries Diseases and Dangerous Occurrences Regulations 2013 in the UK. Therefore, a formal reporting system for spills is required to record and assist with legal requirements.
In case of doubt, it is better to report an incident that looks like it may meet the criteria than not report it at all.
Systematic reporting of spill incidents helps to detect any adverse trends and identify underlying causes. After a serious near-miss or incident, a formal summary of lessons learned is good practice, taking care to keep it simple and accurate and avoid naming individuals.