39TH ANNUAL CONFERENCE, Marrakech, Morocco, 6-10 March 2000WP No. 163Specific Medical Matters |
Introduction
This subject became part of SC4’s working programme at the Santiago de Chile Conference 1999. Information regarding controllers having their licence withdrawn for medical reasons (diabetes and tinnitus) was received during Conference.
Controllers are medically screened prior to beginning an ATC career in accordance with worldwide medical requirements given in ICAO Annex 1. However, national differences exist. According to this screening, controllers should generally be of better health than the average person in the actual country or region.
The controller occupation is known to be stressful, conducted as shift-work and with a considerable amount of electronic equipment at the working positions. Stress and shift-work are known to have adverse effect on health in a general way. Radiation from electronic equipment has a biological effect, but any possible health consequences from this are not yet scientifically established.
SC 4 has approached the task given by the Santiago Conference in the following way:
- Observed the most common medical reasons why controllers lose their licences;
- Researched possibilities for using medication to “control” the effects of illness to the extent that a license can be held or regained;
- Searched for information on possible links between our working environment and illness;
- As a result of this research, this WP present a few examples of investigations conducted into possibly dangerous working environments.
Discussion
The top five medical reasons why controllers lose their licences for in Europe are heart and cardiovascular disease, high blood pressure, hearing loss, tumours and cancer, and neurological disease.
The possibility of using medication to “control” the effects of illness to the extent that a license can be held or regained varies on an individual basis, and only general guidelines can be given in this WP.
High blood pressure may normally be controlled through medication. However, the risk of developing serious heart and cardiovascular disease, may result in a prolonged period without a licence.
Heart disease resulting in surgery generally leads to a permanent loss of licence. New technology and medical methods can make a significant difference for the possibility of an individual regaining his/her licence.
Hearing loss is normally caused by permanent damage to the ear(s). Tinnitus (continuous ringing in the ear) can be of a temporary nature, but no specific medication as such is known to help affected controllers to regain normal hearing. Several countries allow controllers to demonstrate sufficient hearing abilities at the actual working position, if a designated audio test is failed by a small margin.
Neurological disease, such as Multiple Sclerosis (MS), Parkinson’s disease, Epilepsy etc. will result in a permanent loss of license as soon as the clinical symptoms are severe enough to affect the individuals working ability as a controller.
Tumours and cancer will in most cases automatically result in a loss of licence. The licence will very rarely be regained during treatment. Individuals recovering well after such treatment and medication, can regain their licences on an individual basis.
Diabetes can be defined as either type I or type II. Diabetes type I results in loss of license. Type II can normally be controlled through diet and medication, and licence can normally be held on an individual basis for some time.
SC4 has searched for information on possible links between our working environment and illness resulting in loss of licence.
In our discussions with agencies responsible for medical certification of air traffic controllers, it has been apparent that a survey conducted of and among IFATCA MAs cannot pretend to be scientifically valid as such. In order to be scientifically valid, a control group will have to be established and differences in age, working environment, personal economy, lifestyle etc. has to be corrected for.
For this reason we have limited our discussion to known examples in which affected controller(s) have lost their licence(s), and where a possible link between our working environment and illness might exist or is suspected to do so. Such knowledge could be used by MAs to encourage employers to change possibly dangerous working environments.
Additionally, experience can be shared on how investigations in some countries are carried out to reveal possible links. Such investigations can also be necessary in order to remove any doubt that a particular working environment is not affecting controllers’ health in a significantly negative way.
In Bulgaria 20 controllers developed diabetes during a very short period of time. No further information has been available, despite several attempts.
In UK an incident with strong weather interference involving a controller using a headset, resulted in hearing loss probably as a consequence of exposure to strong noise (acoustic trauma). The affected controller has continuous tinnitus, resulting in loss of licence. The controller states that the hearing loss is a result of the working environment using a headset and exposure to strong noise because of weather interference for about 10 minutes.
European legislation, in UK named “Noise at Work Regulations”, sets certain noise limits above which countermeasures have to be taken.
Following the incident, an investigation into the unit’s equipment, including the type of headsets being used, revealed no definite connection between the technical standard and the reported hearing loss. This conclusion is based on measured noise levels from the recording of the reported weather interference, that are below the limits set in “Noise at Work regulations”. (Institute of Sound and Vibration Research, Southampton 1998)
Tumours and cancer can be caused in part by radiation. Prior to the relocation of the new Oslo Centre, concern was expressed in relation to the level of electromagnetic radiation. The Centre is built to comply with military standards, i.e. radioactive radiation will not penetrate into the building. With large quantities of electronic equipment, some of it expected to create significant levels of electromagnetic radiation, the possible problem was; would the radiation created remain within such a closed construction? If so, the working environment could possibly be compared to working inside a giant microwave oven.
An investigation into this “giant microwave oven theory” was conducted by an independent body. Radiation from electronic equipment is of a non-ionising type (not radioactive), and most of the equipment had levels of electromagnetic radiation below European standards. Some of the video monitors had levels of radiation that did not meet the standards, and they where screened. (NEMKO1996). The biological effect of being exposed to electromagnetic radiation is mainly the thermal effects on (parts of) the body. The established standards have conservative limits to ensure that any temperature rise that can damage health, is avoided. (Norwegian Radiation Protection Authority, 1997)
The Oslo study was followed up closely by local management, with detailed information given to the controllers through their representatives. Because no scientific studies conclude that exposure to electromagnetic radiation is absolutely not harmful, management made it clear that pregnant controllers could be exempted from working with this kind of equipment, if they felt uneasy with it (prudent avoidance).
Conclusions
Medical requirements for controllers are regulated in ICAO Annex 1. National differences exist, and a worldwide survey into the reasons why controllers have their licences withdrawn, will be very complex. In addition, such a study cannot be presented as scientifically valid.
From the available material, there is no evidence that controllers are over-represented in any specific disease, compared to the public not exposed to our working environment.
Possibilities for using medication to “control” the effects of illness to the extent that a license can be held or regained varies on an individual basis, and no specific guidelines can be given in this WP.
MAs could seek, or get their employers to provide, independent investigations into loss of licence cases where the working environment was suspected to be partly or entirely to blame for the medical situation of the affected controller(s).
Knowledge from such investigations is important for the psychological well-being, and could be used to improve working environments, and to support the affected controllers. The psychological effect is particularly important in respect to pregnant controllers and their concern over radiation levels. The application of the prudent avoidance principle in such circumstances is of great importance.
Recommendations
This paper to be accepted as information material.
References
MD Per Orva, Head of Norwegian Aviation Medicine Centre, Oslo.
Statens Staalevern (Norwegian Radiation Protection Authority), Norway.
European Standardisation Organisation CENELECs, pre-standard ENV 20166-1 “Human exposure to electromagnetic fields. Low frequency (0kHz to 10kHz)” and ENV 50166-2 “High- frequency (10kHz to 300GHz)”.
Noise levels from headsets at LATCC, Institute of Sound and Vibration Research, Southampton, October 1998.
MD Per Snorre Lingaas, Aviation Medical Examiner, Oslo.
Last Update: September 28, 2020