The problem with Cabin Air Quality

For many years there has been a hidden debate about Cabin Air Quality

That debate has intensified but still Consumers are blissfully unaware of the problems onboard aircraft

Since 2006, I have had the pleasure to be involved with pilots, crew and passengers on the issue of Cabin Air Quality.

Beneath the ebb and flow of aviation and tourism commentary, there lurks an almost whispered scandal of International proportions.

This scandal has its roots going back to the 1950’s, when air travel was beginning its journey toward mass travel.  Commercial aircraft were fitted with a new environmental control system, bleed-air. 

When we get onboard commercial aircraft, we experience the soothing lights, smiling faces, seating according to your pockets, refreshments from the basic sandwich box to an a la carte menu. But despite these differences and experiences, we all breathe the same air.

I’ve seen over time many commentators talk about stale air, re-cycled air and those within the industry liken environmental conditions to being no different to being in your office or your home.

What very few people discuss in the broad media, is the real story of how passengers, pilots and crew are breathing in a potential cocktail mix of toxins that, come from the aircraft engines which cause serious health problems.

Most people are completely oblivious to the fact that the air they breathe onboard is actually syphoned from the aircraft engine and passed through coolers and to a degree filters and introduced into the aircraft cabin and cockpit; that is bleed air.

Bleed-air was introduced as an engineering solution to reduce the weight in an aircraft by removing non-bleed-air equipment, thus lightening the load. 

Whilst the subject is not hotly debated in open public forums, I can assure you that the Aviation Industry, their Insurers and Civil Aviation Authorities are keenly aware of the potential of contaminated air in aircraft to disrupt the Industry.

All makes of commercial aircraft are fitted with the bleed-air system, with the exception of one, the Boeing 787 Dreamliner.

I am certain that those in Boeing would not accept that the Dreamliner’s introduction to our choice of aircraft, is not as a reaction to this hidden debate, but as a recognition that bleed-free technology, along with the new technology of the Dreamliner, produces a quieter, more efficient and cleaner and therefore more beneficial experience to passengers and crew; they would no doubt argue its about creating a new choice for the Industry and about giving people a choice about the aircraft they would like to fly in.

But coming back to the bleed-air models, they are still rolling off the production lines and conceivably, even if solutions are found for newer models, it is anticipated that the current stock of aircraft in-service will be with us for another 40 years.

That’s 40 more years where passengers and crew will be exposed to the potential of contaminated cabin air; that’s 40 more years where passengers and crew will report and add to the already mass of evidence of the ill-effects of exposure; that’s 40 more years of ineffective regulation and enforcement of what little there is.

To help you understand the state of “regulation” it is best to describe the current state of “regulation” in Europe, but I will add, the same issues are found throughout the world; it is not solely an European problem.

Regulation for the production of aircraft, their operations, the operations of pilots and crew, cargo and baggage and the carriage of passengers is held within a Basic Regulation. Regulation in European terms means that it is adopted by each Member of the European Union without the need for individual national parliamentary action.

The basic regulation is extensive and it is referred to as “Hard Law”, in other words, it must be complied with.

But Basic Regulation defers to and is supported by Acceptable Means of Compliance, Alternative Means of Compliance and Certification Standards; all of these are referred to as “Soft Law”. These ‘soft law elements are really Standards, they are not obligatory and therefore not laws, but to comply with Basic Regulation you need to show that you at least can demonstrate that you are doing something to satisfy your Basic Regulation obligations.

The difficulty with all of these differing forms of Regulation is enforcement. The general view is that certainly up until now, European Aviation has not had a strong enforcement regime, but this may change with the advent of the new Basic Regulation, EU 2018/1139, which will create a team and structure of inspection, throughout the European Union, to examine whether a manufacturer or airline is complying with “Regulation”; I suspect that it will be some time before the full affect of the Regulation’s intent will be felt.

More pressing is the debate about “Designors” and “Designees”; what on earth are those you may ask? 

A good but important question in the field of aviation manufacturing. 

The best example can be found in the recent Boeing 737 Max aircraft crashes. In the aftermath of these tragedies, the Boeing Company has come under intense scrutiny about its manufacturing processes by the Federal Authorities in the United States. 

One aspect of their enquiries centres around the use of “Designors” and “Designees”, through the various stages of manufacturing and certification, that declare that an aircraft is fit to fly. 

In this case it would appear that the “Designors” were the Federal Aviation Authority who deferred their certification mandate, in other words their responsibility to certify each part of the aircraft. They passed that role, apparently onto company employees or sub-contractors, who it is alleged certified the aircraft in question as being fit to fly.

This is an important aspect of aviation safety, because we take on trust that all before us have done absolutely everything necessary to ensure that the metal tube we will be flying in is safe to travel on. 

The use of “designors” and “designees” therefore could be argued to be yet another extension of the “Soft Law” I have referred to.

It may interest listeners to know that I have pressed the European Aviation Safety Agency on the “Designor” “Designee” point and I will be quite honest with you, the response I have received is somewhat confusing, it appears to suggest that the same methodology exists but they use different terminology. I have asked colleagues to help me decipher the letter, but even they are struggling with the explanation; I sense that this will be the topic of another podcast!

But, coming back to Regulation, I want to draw your attention to something else that’s popped up on my radar.

I understand that there is currently a small consultation being carried out by the UK’s Civil Aviation Authority (the CAA) into light aircraft and Carbon Monoxide; this follows on the heels of the tragic crash of the aircraft carrying the footballer, Emiliano Sala. 

It appears that when the aircraft was located on the sea-bed, they found a very strong indicators that Emiliano had been overcome by Carbon Monoxide. 

As any responsible Civil Aviation Authority would, they ordered a consideration of the issues along with a small consultation about the warning notice to be circulated to the owners, operators and pilots of light aircraft.

Light aircraft generally do not have the same environmental control systems as their larger commercial cousins. Unless they have air conditioning units installed (which for weight reasons tends not to be the case), a lower altitude and air vents provides the air that its occupants breathe. The engine operates like most aviation engines, fuel, air and engineering provides thrust to the aircraft and its waste products are removed by an exhaust system. The concern appears to be centred around the exhaust system and the potential for seals around the bulkhead to fail or be inadequate, presumably through concerns over maintenance. 

In the proposed notice they refer to several documents some of which are “Civil Aircraft Airworthiness Information & Procedures” or CAPs for short. In one CAP they refer to, CAP 562, it defers to European Law as being the principal source of Regulation, but interestingly the proposed warning notice only makes a passing reference to EU Law in the ‘other reading’ section. They direct the reader of the proposed notice to the section on Carbon Monoxide in CAP 562.

It is perhaps worth reading to you some of what it says; it states at Leaflet B-190:

“This Leaflet describes the nature and effects of carbon monoxide (CO) and outlines the main causes of this type of contamination. It gives only general guidance on the inspections, tests and repairs which should be carried out in order to minimise the dangers of such contamination to crew and passengers….It is stipulated in the Requirements that CO should not be present in occupied compartments in quantities exceeding 50 parts/million by volume, for any period exceeding five minutes: maximum allowable concentrations are also prescribed for other noxious substances such as fuel, oil, de-icing and hydraulic fluids, fire extinguishing agents and the fumes given off by other materials when they are heated…When doubt exists as to the extent of contamination of the air in the crew or passenger compartments, a test should be carried out to determine the CO concentration. This test is usually carried out by a sampling process…The apparatus usually consists of a hand-operated bellows, which is used to draw a specified volume of air through a sampling tube, the presence of CO being indicated by the staining of crystals in the indicating portion of the tube”

Thats right, to test for CO they are recommending that you man the pumps and extract a sample into what is after all a glorified breathalyser test!

Think about this.

No conversation about the installation of CO alarms.

No conversation or re-emphasis for owners, operators and pilots of light aircraft to record and report all fume or indeed smoke events.

Only that any remedial actions should be supported by the manufacturers manual.

As you’ve heard, they make a reference to the holy grail of any conversation about contaminants in aircraft, chemical threshold limits. 

No recognition that chemical threshold limits have reached their sell-by-date and have moved onto clearer discussions about sensor technology along with a recognition of low-level-exposure to contaminants.

Consider this.

In the USA, congress has passed a Bill whereby operators of Civil Commercial aircraft will have to install CO alarms, so if there is a requirement to install CO alarms in larger aircraft, why, after the tragedy of Emiliano Sala is the CAA not urgently recommending the installation of CO alarms in all light aircraft, what ever about their larger relations?

Perhaps the answer lies in the phrase “Soft Law”, forever condemned to allow best judgement and practice to prevail.

As I said at the beginning, this International scandal has many roots but it is the ultimate end-users, the pilots, crew and passengers, of whatever aircraft, that has to bear the load of regulatory failure.

Surely the time has come for all stakeholders, particularly state and trans-national stakeholders, to recognise that a more intelligent approach to aviation is required; we shall see what happens next!

(This commentary is also set out in the @ConsumerFrank Podcast which can be heard here)