Safe Slurry Handling
In the next few weeks the last of the slurry for this year will be spread on farms by many farmers and contractors before the October 15th deadline. Francis Bligh & Tom Fallon, Teagasc have important advice on staying safe around slurry, in particular when agitating slurry and emptying slurry tanks
Mixing and spreading slurry are high risk activities. Drowning and gas poisoning together with the potential of crush injuries from machinery are the main risk areas.
Children and older farmers
Children and the elderly are at particular risk from slurry related accidents. Health and Safety Authority data show in the period 2010-2019, 5% of child fatal accidents on farms were caused by drowning/gas. In the same period 6% of deaths to elderly farmers were caused by drowning/gas. Only persons involved in the job should be present. Children must be supervised in a safe play area.
Microorganisms help break down the slurry and make the nutrients more available but this process also produces toxic gasses. Carbon dioxide, ammonia, methane and hydrogen sulphide can be released in high concentrations when agitation commences. Hydrogen sulphide is a very dangerous gas. It smells like rotten eggs at low concentrations but you cannot smell it at high concentrations. One breath at this level can be lethal. Methane is a flammable gas and farmers have experienced fires or explosions when this gas came in contact with a spark. Avoid smoking, welding and cutting metal close to slurry tanks.
Evacuate and ventilate
Before starting the job take some time to plan and prepare. Make sure farm pets are put into a secure area. Inform all family members and other people that may be around the farm that slurry agitation is taking place. Make sure all the animals have been removed from the shed. Open up all doors and air flaps to provide good ventilation. If the weather is calm and there is very little air flow delay agitation to a later time or to a different day. It is good practice to have another person present during agitation. For at least the first 30 minutes after agitation commences stay well clear of the area around the agitator and do not allow access to the shed.
Indoor agitation points
Mixing slurry using agitation points inside the shed is highly dangerous and MUST be avoided.
What are the options or remedies for farmers with indoor agitations points or a combination of indoor and outdoor agitation points? The first three options are all eligible for grant aid under TAMSII which is currently open for applications. The last tranche of TAMS II closes on 5th November 2021.
Option 1: Install outdoor agitation points
Tanks can be extended to provide an agitation point/s outdoors.
Option 2: Install a slurry circulation pipe
A fixed slurry circulation pipe is used to pump slurry from an outside agitation point to a location within the slurry tank to aid circulation of the slurry. Details of this can be found to download here S123D Accepted Simple Aeration Systems for Grant-Aid - January 2019. To work well the slurry should be easily pumped and be of reasonable uniform consistency. For animals on a low DMD diet it is advised to start the winter by placing 0.3 to 0.6m of water at the bottom of the tank. This system is still relatively unproven but may be a viable option in some situations where appropriate agitators and slurry pumping equipment is available.
Option 3: Install a slurry aeration system
This system periodically pumps air through a series of pipes that are placed at the base of the tank. As the air bubble rises to the surface it churns the slurry thereby mixing it. This system removes the need to use mechanical agitators and lowers the likelihood of gas build up. This system is expensive to install but the running costs are low. It is important to note that this system may contradict the national requirement to reduce gaseous losses from slurry especially ammonia.
Option 4: Slurry additives
There are many additives on the market that will assist the agitation process. The feedback from farmers that have used these additives is very positive.
Teagasc advisers can advise on these options and on associated TAMSII grant applications. You can contact any of our Teagasc offices using this link Teagasc Advisory Regions here
Useful tips to reduce accidents when spreading slurry
- Has the tractor and slurry tanker been serviced recently
- Check tyre pressure in both tractor and slurry tanker and the braking system
- Check attachment mechanism of tanker for wear.
- Clean windows on the tractor, check mirrors, put cones/traffic warning system on the road
- Cut back vegetation at gate entrances to improved visibility
- Can you adjust field openings to avoid having to stop on public roads to open gates? (or perhaps they can be opened in advance of the spreading operation)
- Check field conditions and avoid spreading on steep ground where the surface has recently become wet
The Health and Safety Authority (HSA) have produced a number of videos focused on safety with slurry:
The full list of items can be found on the TAMS II Animal Welfare, Safety and Nutrient Storage Scheme terms and conditions Annex B at the back of the booklet which can be found on the Department of Agriculture, Food and The Marine website. Every farmer should make themselves aware of the items on this list to avail of grant aid if they plan on purchasing any of them. The Department costings and marking sheets are also available online or by contacting your Teagasc Advisor or Agricultural Planner. Grant aid is not all about large investments, smaller items are also covered.
Authors: Francis Bligh is a Teagasc Health and Safety Specialist and Tom Fallon is the Teagasc Buildings & Infrastructure Specialist.