Process safety: the rules of personal protection

Throughout the process industries, fire, gas and chemicals can create some of the most dangerous hazards that engineers have to contend with.

When it comes to fire, there is clearly a risk associated with intense heat and burning.

However, another major problem associated with fire is the emission of carbon monoxide, which has a uniquely damaging effect.

When carbon monoxide is inhaled, alveoli in the lungs will ignore oxygen, and instead opt for the poisonous gas. This gas can then get into the blood stream, which can lead to hypoxia.

Hypoxia can cause death within four minutes, says Keith Sillitoe, health and safety advisor at the British Safety Council. “There are no warning signs with hypoxia – it’s a silent killer.”

Line of defence

Today, modern fire detection systems can be combined with carbon monoxide detection systems to help ensure workers are alerted to a hazard within seconds of it being detected, Sillitoe says.

“Engineers can also wear specialist breathing apparatus and heat-treated clothing. Some versions of this clothing have the capacity to defend against chemical splashes and electrical arc as well.”

Compressed gases, meanwhile, which can be liquefied, nonliquefied and dissolved, pose different threats to fire. “Clearly, compressed gases are hazardous because they are under pressure. However, the worst offenders are dissolved gases such as acetylene,” Sillitoe warns.

He says that once the decomposition process for this type of gas begins, it cannot be stopped. The outcome of this process is heat, which would eventually lead to an explosion.

“Fortunately there are levels of protection. Modern gas cylinders, which house products like acetylene, are designed with blowout disks and pressure valves.

“However, if these get rusted, their reliability can be called into question,” Sillitoe says.

Inhaled chemical vapours can also cross into the bloodstream affecting other organs, potentially causing cancers and damage to the central nervous system

Alan McArthur, technical supervisor at 3M

Like fire and gases, chemicals also pose a unique set of risks. They are considered hazardous on four main fronts.

Chemicals can be toxic, corrosive, harmful and an irritant, and the risks can vary, dependent on the substances being handled.

“In terms of personal protection, you have got to consider what the property of the chemical is, and what the route of exposure could be,” says Alan McArthur, technical supervisor at personal protective equipment manufacturer 3M.

According to McArthur, engineers working with chemicals risk exposure via inhalation, which, dependent on the chemical, can result in problems with the respiratory system and damage to the lungs.

“Inhaled chemical vapours can also cross into the bloodstream affecting other organs, potentially causing cancers and damage to the central nervous system.”

Chemicals can also damage the skin and may enter the bloodstream via that route.

Handle with care

To avoid these risks, companies should employ a hierarchy of control, McArthur advises.

He says one of the most important things to consider is the necessity of handling the chemical in the first place.

“First and foremost, companies should ascertain whether they can eliminate the chemical and use something less harmful.”

However, McArthur is quick to point out how unlikely this option is for many companies in the process industries.

“Assuming the use of chemicals is a necessity, you must then consider enclosing the process and isolating the person from the potential hazard. Where this is not practicable, the next level of control is typically achieved via the installation of an extraction system.”

Fortunately, most established industrial premises will have a ventilation system of varying levels of efficiency to help reduce exposure to chemicals, McArthur adds.

The next steps an employer should take are administrative.

McArthur says that these steps, which are designed to further minimise the risk of exposure, can include job rotation; appropriate signage; and preventing people from gaining access to certain areas in the plant.

The technology is definitely there. PPE works mainly for compliance, but the right selection of PPE is really important

Prabhu Soundarrajan, leader of Honeywell’s connected solutions business

Only once these steps have been followed should a company consider the use of personal protective equipment (PPE), McArthur says.

“PPE is generally intended as a last resort. It should be seen as a buffer that mops up any residual risk. In the hierarchy of control it usually finds itself at the bottom,” McArthur says.

However, in some instances engineering controls may not be feasible.

For instance, when an engineer is conducting maintenance work, McArthur says, PPE may be more of a necessity and may have to serve as the primary control.

But regardless of the situation, McArthur says worker safety and long-term health must always be the primary concern.

And while many companies and some specialist engineers are very good at understanding risks, there can be a lack of adequate awareness elsewhere in industry.

“I sometimes see issues associated with familiarity. For example, some engineers do not wear PPE correctly,” Sillitoe says.

Knowledge is key

One of the major obstacles in this instance is poor product knowledge, he adds.

“Some engineers aren’t aware of the hazards, which means they may not have a good understanding of the equipment they actually need.”

Prabhu Soundarrajan, who leads Honeywell Industrial Safety’s connected solutions business, says that in terms of obstacles for companies adopting best practice, it really comes down to training the operator.

“The technology is definitely there. PPE works mainly for compliance, but the right selection of PPE is really important,” he says.

There are also issues associated with maintaining PPE.

“If overalls are left on the floor, the dust they collect will get into the atmosphere when the next engineer comes to wear them. Clearly, that creates a hazard,” Sillitoe says.

So where does the buck stop?

For Sillitoe, the Health and Safety at Work etc (HSW) Act, which is the primary piece of legislation covering occupational health and safety in the UK, is very clear.

For example, Section 2 discusses vicarious liability, which looks at the duty of the employer and the levels of protection they must offer employees.

“Section 6 of the Act places duty on the product manufacturers themselves. PPE designers have to make sure their equipment does what it says on the tin,” Sillitoe says.

The HSW Act also scrutinises employee responsibility. Section 7 places a duty on the employee to co-operate with their employers.

“Clearly there is a shared responsibility when it comes to worker safety,” Sillitoe says.

“All three parties – employers, equipment manufacturers and employees – have to work together,” he adds.

If you have a practical measure to protect against ill health and injury, failure to implement it correctly could cost you a lot more than the price of a dust mask

Keith Sillitoe, health and safety advisor at the British Safety Council

They should also be considering the cost of safety.

Research consultancy group Frost & Sullivan suggests the PPE industry will be “very different” by 2030.

“Winners” of the PPE industry will be those who drive innovation and create “smarter” PPE products, Frost & Sullivan says.

In the current climate, this market disruption is caused by pricing pressures and the increasing commoditisation of products, the group adds. Unfortunately, cost concerns can be really damaging for a business and its employees.

“An FFP3-rated disposable dust mask costs roughly £25-£40, for example,” says Sillitoe.

However, if a worker contracts mesothelioma from exposure to asbestos it will likely cost a company thousands of pounds in compensation, legal fees and increased insurance premiums, he adds.

“If you have a practical measure to protect against ill health and injury, failure to implement it correctly could cost you a lot more than the price of a dust mask.”