Welsh farmers warned over risks from deadly gases in slurry

With a little-known deadly gas emitted by slurry responsible for fatalities in farming every year, the Wales Farmer Safety Partnership (WFSP) is raising awareness of the risks that exist, even in open spaces.

Hydrogen sulphide can be just as deadly outside as it is in confined spaces and its toxic fumes can overcome farmers within seconds, warns WFSP Ambassador, Alun Elidyr.

“There is no such thing as a safe slurry tank,’’ he insists.

It is more important than ever that farmers are aware of the risks of the gases in stored slurry with the new Control of Agricultural Pollution Regulations in force, with closed periods prohibiting the spreading of slurry and organic manures ranging from 1 August – 31 January, depending on land and crop type.

Slurry contains multiple gases including methane, ammonia and carbon dioxide but the most dangerous of all is hydrogen sulphide.

Just two or three breaths of this is sufficient to disorient or overcome a person, says Alun.

“This gas is heavier than air so it sits a metre or two above the surface of slurry. Anyone putting their head in that space, especially when a tank is agitated, can breathe it in without realising it,’’ he explains.

“It has no smell so you won’t be able to tell if you have been exposed to it.’’

Agitation, when the tank is mixed to combine the solids and liquid element, is particularly dangerous because this process releases the gases.

Livestock can also die from inhaling these fumes.

Alun says it is vital to adopt the ‘stop and think safe’ mindset before starting a job involving slurry, as is the case with any other farm task.

“Plan your work, that plan is your risk assessment,’’ he advises.

“It doesn’t have to be written down but the effect of having considered it is the most important process in your day, whether it is working with slurry, handling livestock, dipping sheep, working at height.’’

Financial and labour challenges and changes to farm practices mean that farmers often work alone and this presents its own risks in these situations.

Alun reckons that a ‘buddy’ system, which is commonplace among foresters and involves lone workers checking in at agreed times with someone, would be highly beneficial for many farming operations, including slurry work.

“The ideal situation is that no farmer should be working alone, especially in high-risk situations, but when they are I know of instances when the buddy system has saved lives.’’

Alun stressed the importance of following a safe system of working and assuming that hazardous gases are present around slurry, and to mitigate the danger.

A slurry gas monitor, which can cost less than £200, is advised, although Alun cautions that they shouldn’t be completely relied upon.

“It is a grey area because anything over 200 parts per million (ppm) can be a danger but there might be a breeze blowing through a shed with underground storage and you don’t feel the effects but suddenly a bubble of gas rises and the level shoots up to 500ppm which can have a life-threatening effect.”

He says farmers owe it to themselves and to the industry to do everything possible to prevent accidents from happening.