Make room to breathe easy

Published: 11th Oct 2013

In January 2, 2006, a catastrophic explosion ripped through the Sago Coal Mine operated by Anker in West Virginia, USA.

Twelve miners lost their lives and one was seriously injured after becoming trapped underground. The sole surviving miner reported that at the time of the emergency, the portable breathing units provided by the company did not appear to function correctly, which contributed to their tragic decision to abandon an escape attempt and instead await rescue. Post-incident testing of these units, however, revealed that they did, in fact, function correctly.

What caused these operators to make this fatal error and what lessons can other industries learn to ensure personal protective equipment (PPE), such as self contained breathing apparatus, is used effectively by employees?


Self contained breathing apparatus (SCBA) is used in various settings, ranging from emergency situations such as underwater helicopter escapes (Brooks et al, 2010) and loss of containment events (Wang et al, 2011), to operations such as working in confined spaces (Knight & Orsnell, 2005). Moreover, use of SCBA is now commonplace in industries such as oil and gas, mining, and emergency response.

SCBA differs markedly in its function and form, although can be generally described as a device that provides uncontaminated air in hazardous operating environments. SCBA consists of a tight fitting and impermeable faceplate, with hoses that connect to a storage tank containing pressurised air in various mixtures of oxygen, nitrogen, and other atmospheric gases.

Importantly, SCBA requires special training to use effectively and also increases the physical and psychological intensity of work tasks.

Unfortunately, the Sago Coal Mine disaster is but one of many past events where SCBA has been implicated in serious injuries and fatalities. Although the percentage of incidents where SCBA has been identified as a contributing factor is relatively small (Bellamy et al, 2010), as a piece of PPE, SCBA forms one of the final lines of defence against occupational hazards. It is therefore critical that when SCBA is required to perform work safely, the device is worn appropriately and functions as expected – protecting the operator from harm.

Subsequent investigations of safety incidents and large scale catastrophes reveal a slew of equipment, operator, and organisational failures associated with the incorrect use of SCBA. Indeed, post-incident investigations at the Sago Coal Mine revealed multiple deficiencies not only in the knowledge, skill, and situational decision making of the trapped miners, but also with the company’s training practises, operating procedures, and general approach to safety management (Kowalski-Trakofler, Vaught & Brnich, 2008).

In addition, a study of more than 9,000 safety incidents reported in the Netherlands identified common trends in the causes and outcomes of occupational injuries (Belamy et al, 2010). The researchers determined that SCBA-specific incidents where breathing of contaminated atmosphere resulted in a reportable injury or fatality were caused by a range of factors – some of which were outside the operator’s control. These causes included:

• Equipment-related faults or design inefficiencies

• Missing or incomplete procedures

• Low operator competence or motivation

• Lack of SCBA availability in areas where it was required

Finally, a study carried out in the chemical shipping industry drew on human and organisational factors to ‘unpack’ the contributing factors to loss of containment events (Wang et al, 2011). Within the situations analysed, which involved failures on the behalf of operators to correctly don SCBA when required, multiple and far-reaching contributing factors were identified. These factors typically began with unsafe acts of operators, e.g. failing to wear SCBA and inadequate assessment of risk, followed by poor supervision, e.g. absent or unclear work instructions and lack of direct oversight, and ended with deficiencies in OHS management, e.g. inadequate safety inspection practises and emergency drills.

One conclusion we can make from these studies is that correct use of SCBA goes far beyond the individual operator. Like most performance issues in contemporary safety management, the answer to the SCBA acceptance and use problem lies within the complex interplay between regulators, executive management, frontline supervisors, workers, equipment, and environmental conditions. Only by considering how these factors operate across and within an organisational system can leaders and OHS professionals ensure that SCBA is used appropriately and to its fullest extent.

Integrating trends and patterns across safety research, we now explore three core factors that have been found to contribute most to SCBA usage in the workplace: equipment design, operator competence and motivation, and organisational occupational health and safety (OHS) management.

Equipment design

SCBA is typically used in harsh and noxious environmental conditions where even momentary exposure to an unfiltered atmosphere can result in serious injury or death. One example is maintenance work carried out within confined spaces such as storage tanks, where not only can the level of breathable air drop to dangerous levels, but, depending on the materials being stored, toxic vapours arising from residue and by-products of task activity may also be present (Kletz, 1999).

In addition, SCBA use is often accompanied by operating environments that are hot and humid, which increases the physiological burden on operators and pushes SCBA to its operating limits (Brown & McConnell, 2012). Lastly, most work tasks being undertaken by SCBA-equipped workers require prolonged physical activity, which can increase muscle fatigue and reduced performance.

From the operator’s perspective, use of SCBA can produce a range of undesirable physiological and psychological effects that contribute to acceptance and use in the workplace:

• Perceptions of increased breathing difficulty

• Limb discomfort

• Reduced locomotion muscle blood flow

• Shallow and rapid breathing

• Reduced exercise tolerance level

Together, these effects not only present challenges to operator comfort, but also the ability to perform effectively in situations that require considerable dexterity and endurance.

To understand the effects of these operational characteristics on SCBA use, a physiological perspective is needed.

Researchers have estimated that the body’s energy expenditure increases by 1% with every kilogram of extra weight (Dorman, 2007). Combining the weight of protective clothing and the often bulky external SCBA air tanks, weighing more than 11kg when filled, (Bakri et al, 2012), considerable muscular and metabolic strain is placed on the operator.

Also, poorly designed SCBA can markedly change an operator’s centre of gravity, increasing the risk of slips and falls (Kroemer & Grandjean, 1997). The harnessing and distribution of weight of SCBA attachments have been shown to induce changes to normal breathing rhythm and increase respiratory muscle fatigue – particularly when performing highly physical work activities (Butcher et al, 2007). Over the long term, repetitive and prolonged use of poorly designed SCBA equipment may lead to weakened respiratory muscles and in turn, spine trauma and chronic back pain if left untreated (Brown & McConnell, 2012).

With the objective of addressing these issues, the science of ergonomics has contributed much to the advancement of SCBA technology, as well as operator acceptance and use. Design innovations such as positive faceplate pressure to prevent accidental inhalation of atmospheric contaminants (Bryant et al, 2011), and ultra-portable (Brooks et al, 2010), and slimline backpack-based units (Bakiri et al, 2012) have reduced the physical demands of SCBA equipment. The menagerie of commercial SCBA devices available, however, means that organisations must make careful decisions in the selection and implementation of these technologies.

Specifically, organisations should ensure that SCBA equipment has been tested in field conditions and is certified by institutions such as OSHA. Further, companies should conduct their own evaluations of sample units to ensure that the equipment is a good fit to the range of tasks being completed by their workforce. Finally, a thorough needs’ analysis should be undertaken to ensure that the most appropriate SCBA device is selected – this analysis should carefully consider the context(s) in which the SCBA unit will be used and determine the necessary functional requirements in light of existing asset and task characteristics, e.g. maximum time required to reach a lift raft in the event of loss of containment. Taking a careful and considered approach to the selection of SCBA will help to encourage uptake among operators during the implementation phase.

Operator competence and motivation

Despite marked improvements to the design and function of SCBA over the past decade, analysis of safety incidents and field testing studies have revealed that operators’ subjective perceptions of device usability and comfort, as well as their level of technical SCBA competence influence usage intentions.

Following the Sago Coal Mine disaster, analysis of the perished miners’ SCBA revealed that the devices had indeed functioned as intended and were only partially depleted of oxygen. The sole survivor reported that the miners shared mouthpieces and did not allow sufficient time for the units to start the necessary oxygen-generating chemical reaction before discarding them as non-functional (Kowalski-Trakofler et al, 2008).

Finally, the investigators proposed that the trapped miners may have failed to maintain a steady rate of breathing – depleting the oxygen at a faster rate than it could be generated and ultimately interfering with the unit’s proper function.

All of these contributing behaviours point to a lack of knowledge and skill on behalf of the operators, which in turn, points to deficiencies in training and OHS management. Indeed, the Mine Safety and Health Administration’s (2005) official investigation team found that the surviving workers received training in SCBA use only once a year and most operators did not feel confident in using the devices. These issues could have been readily avoided by conducting more frequent training that provided information about how the devices functioned and included simulation of realistic operating conditions.

SCBA is a highly technical device, as evidenced by the significant training requirements detailed by professional companies offering such services. For basic SCBA devices, operators receive around two hours of theory followed by another two hours of skill development and practise (Brooks et al, 2010). Ideally, this practise occurs in realistic settings, such as in helicopter underwater escape training (HUET) commonly performed in the offshore oil and gas industry.

Simulations and other realistic experiences may be crucial in situations where SCBA is required, particularly during events that occur infrequently or involve pressure. Under stressful conditions, the human response is highly primitive: various hormones are released which trigger a cascading effect of physical and mental changes. In effect, the ‘flight or fight’ response kicks in, which has a marked effect on human performance via changes in blood flow, breathing, concentration and attention, memory, and emotional stability (Kroemer & Grandjean, 1997). As many of these functions impact on breathing and therefore, the normal operation of SCBA, preparing operators for these conditions becomes imperative.

Motivation and other attitudes also play a part in driving (in)correct SCBA use. In some cases, operators may simply become habituated to certain ways of working and hence neglect the wear of all required PPE. In other cases, operators may either fail to recognise that a hazard is present, or underestimate the level of risk in a given situation (Wang et al, 2011). Psychological research done in organisations has established that these patterns of thinking are less about the individual operator and more about the broader social context influenced by teams, supervisors, and executive management (Christian et al, 2009). Additional skills and knowledge training are therefore only part of the solution – leaders and co-workers can play an active role in establishing a social context that promotes effective SCBA use.

In sum, operators are obligated to participate fully in SCBA training and ensure that they possess a minimum level of competence to use SCBA effectively on the job. In turn, organisations have complementary obligations to provide such training at regular intervals and under realistic conditions.

Further, organisations must ensure that SCBA training adequately prepares workers for the psychological reality that accompanies emergency situations and equip them with strategies to manage their physical and psychological responses to these events, e.g. cognitive-based safety training.

Finally, both workers and organisations are equally responsible for encouraging correct use of SCBA. Co-workers can remind each other to wear SCBA appropriately and leaders should ensure that correct SCBA use is recognised and rewarded. Through reinforcement of positive behaviours and the development of shared ways of thinking about safety, SCBA usage will improve.

OHS management

At an organisational level, a company’s approach to OHS management manifests in both intangible – e.g. safety culture and climate – and tangible – e.g. inspection practises, quality of safety procedures and training – characteristics. We can think of OHS management as the roots of a tree that ideally should pervade every aspect of operations, from the jobs of frontline workers to the systems used to manage safety at a macro level.

In many organisations, however, these roots are malnourished and few in number. Competing production and quality demands can divert resources away from safety, which has marked effects on worker behaviour, administrative controls, and the availability and quality of equipment such as SCBA.

In the years leading up to the Sago Coal Mine disaster, the site was cited by MSHA (Mine Safety and Health Administration) 208 times for violating industry regulations and 96 of these were considered serious and substantial (MSHA, 2005). Further, the mine had a significantly higher reportable injury rate compared to the industry average.

Together, statistics such as these suggest fundamental problems with the manner in which Anker managed safety at the mine, with the ultimate product being a workforce ill-prepared for emergency situations that required the use of SCBA.

Other studies have shown that unsafe acts such as ignoring SCBA requirements are precipitated by more general organisational factors stemming from ineffective OHS management strategy and implementation. These include:

• Emergency drills failing to cover work areas where SCBA is required, and hence, is not practised regularly under simulated conditions

• Inconsistent enforcement of SCBA safety standards, e.g. supervisors ‘turning a blind eye’ to work risky activities

• Unavailable or out of date SCBA equipment

• Lack of supervision

• Unclear procedures outline when and how SCBA should be used

• Inexperienced leadership

• Habitual risky behaviours such as ignoring or silencing loss of containment-related alarms

• Generally low awareness of hazards and safety issues across an organisation

These problems point to a generally low prioritisation of safety management at the executive levels of an organisation, which filters down to the workforce and results in habituation to unsafe acts, complacency – an ‘it won’t happen here’ attitude – and ignorance of hazards and risk.

OHS management issues are not readily fixable problems. Considerable effort and resolve is required by an organisation to diagnose the issues, mobilise resources, and implement deep reaching fixes that fundamentally improve administrative and social structures.

Organisations engaged in safety-critical operations should consider involving external consultants to ensure that existing systems and practises are examined with ‘fresh eyes’. Further, lessons from other organisations should be shared widely across industries to promote learning and a proactive approach to safety management. Finally, senior management must remain connected to ground level issues by engaging in participative discussions with employees and prioritising safety during budgetary allocations and other high level decisions.


SCBA is only one piece of PPE that organisations in heavy industries utilise on a daily basis, yet contributes to a significant proportion of injuries and fatalities. Given that SCBA is required for operators to perform work in high risk environments, organisations must think carefully about the methods used to select, implement, and review the use of these technologies. For SCBA to be effective, it has to be designed to match the work environment and the task, and fit with the needs of its human operators. Also, SCBA requires realistic and competency-based training to ensure that operators possess the necessary knowledge, skills, and psychological preparedness. Finally, organisations should examine their OHS management system to establish whether current procedures, systems, training, leadership, and the broader safety culture are contributing positively to operator safety performance.

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Published: 11th Oct 2013 in Health and Safety Middle East