Key Visual

Thresholds of thermal damage

26-28 May 2015

Istanbul, Turkey

    The workshop "A closer look at the thresholds of thermal damage" took place from 26-28 May 2015 in Istanbul, Turkey. The Workshop, which was opened to public participation, was jointly organized with the World Health Organization and hosted by the Ministry of Health of the Republic of Turkey. ICNIRP gratefully acknowledges this support.

    A workshop report was drafted by an ICNIRP Task Group and published in Health Physics 111(3):300-306; 2016.

    WHO logo

    In view of updating the guidance on limiting exposure to high frequency (HF) fields, ICNIRP reviewed the current scientific knowledge on the thresholds of thermal damage. The current workshop revisited  the ICNIRP 1998 concept, namely that the health relevant increase of body core temperature is approximately 1° C and a whole-body exposure with an average SAR of 4 W/kg result in a core temperature increase of less than 1°C within 30 min. Details of this concept as well as thresholds for partial/local body exposures are subjects to review.

    Amongst others, the following topics and questions were addressed:
    Definition/Specification of the threshold for thermal damage:
    a) with respect to - the whole body, - parts of the body (limbs, trunk, head), - different organs (i.e. brain, eye, testis, skin etc.) - different tissues (muscle, fat, nerve, connective tissue) b) regarding frequency dependence
    c) with respect to external conditions (cold and hot environment, humidity, clothing)
    d) with respect to internal/individual conditions (interindividual variations, age-dependence, health status, metabolic status, medication, compromised thermoregulation, pregnancy,… )

    Definition/Specification of the health relevant quantity (SAR, power flux density, temperature, thermal dose/CEM43°C, Arrhenius thermal dose rate)

    Is our thermoregulation (evolved to respond to physical work and hot environments) effective in responding to local (internal) HF-induced heating?

    Is the averaging time of 6 min and the averaging mass of 10g of contiguous tissue appropriate?

    Has exposure duration to be taken into account (even at low exposure levels)?


    26 May 2015
    Rüdiger Matthes, ICNIRP
    Emilie van Deventer, WHO
    Assoc. Prof. Murat Gültekin, Director,  Cancer Control Department, Public Health Institute, Turkish Ministry of Health
    Prof. Dr. Tunaya Kalkan Istanbul Cerrahpasa University, Biophysics Department

    Session 1: From thermosensation to thermoregulation - Chair: Eric van Rongen

    Andreas Flouris, FAME Laboratory, School of Exercise Science, University of Thessaly, Greece
    in collaboration with Glen P. Kenny, School of Human Kinetics, University of Ottawa

    Thermoregulation: functional architecture of the thermoregulatory system

    Thomas Voets, University of Leuven, Belgium
    Thermosensation - Ion channels as molecular thermosensors (and the impact on HF heating) 

    Break and refreshments

    Heidi Danker-Hopfe, Charité, Berlin, Germany
    Thermoregulation, sleep and ageing


    27 May 2015
    Session 2: Thermal sensitivities - Chair Rodney Croft

    Eugene A. Kiyatkin, NIDAIRP Baltimore, US
    On the temperature sensitivity of the brain

    Andreas Flouris, FAME Laboratory, School of Exercise Science, University of Thessaly, Greece
    Heat load limitations under normal and stress conditions

    Pavel Yarmolenko, The Sheikh Zayed Institute for Pediatric Surgical Innovation, Washington, US
    Thresholds for thermal damage of different tissues; thermal dose models

    Break and refreshments

    Masami Kojima, Kanazawa Medical University, Japan
    Ocular thermal injury

    Roger Mieusset, CHU Toulouse, France
    Genital heat stress and semen quality



    Session 3: Thermal effects due to HF exposure, HF dosimetry  - Chair: James C. Lin

    Ken Foster, University of Pennsylvania, Philadelphia, US
    (Thermal) mechanisms of interaction between HF and biological systems

    Akimasa Hirata, Nagoya Insitute of Technology, Japan
    Computational age dependence of heating, heating of the eye, relationship between SAR and temperature, thermal model for pregnant woman (ambient heat versus HF)

    Marvin Ziskin, Temple University Medical School, Philadelphia, US
    Frequency dependence of heating, thermal threshold for teratogenicity, reproduction and development, mm-wave exposure of the skin

    Break and refreshments

    Christopher M Collins, New York University School of Medicine, US
    RF pulse sequence and temperature elevation


    Workshop Dinner - Sinan Bey Boat ride

    28 May 2015
    Session 4: Lessons learned from medical applications - Chair: Zenon Sienkiewicz

    Gerard van Rhoon, Erasmus MC Cancer Institute, Rotterdam, Netherlands
    Mild hyperthermia in cancer therapy

    Elizabeth Repasky, Roswell Park Cancer Institute, Buffalo, US
    The role of temperature in cancer immunology

    Theodoros Samaras, Aristotle University of Thessaloniki, Greece
    CEM43°C thermal dose thresholds for MRI

    Break and refreshments

    IEC MT40 Working group
    Manuel Murbach, IT´IS, ETH Zurich, Switzerland
    Tissue heating during MR examination as function of RF exposure and local thermoregulation, consequences for the MR safety standard IEC 60601-2-33
    Johan van den Brink, Philips Healthcare, Best, Netherlands
    Evaluation of estimated CEM43 values attained for realistic use cases under (local) SAR constraints imposed by IEC60601-2-33

    Earl Zastrow/Niels Kuster, IT'IS, Zurich, Switzerland
    Temperature rise due to medical implants

    Panel Chair: Bernard Veyret
    Panel discussion on topics above, including
    How well does the SAR reflect the health relevant thermal threshold?
    How conservative is the reduction factor of 50 in view of the data set presented?
    Reduction factors – as issued by ICNIRP - reflect a safety margin to thermal damage and consider scientific uncertainties like interindividual variability, but are per se not considered as precautionary measures.

    The workshop will be held at the Nippon Hotel, a centrally located venue in the Taksim square area in Istanbul.

    Venue: Nippon Hotel

    Topçu Caddesi No: 6
    34437 Taksim - Istanbul

    More information related to booking your room there and rates will be available shortly.

    How to get there?

    Atatürk Airport transfer

    1. Havatas Bus
    Line: Atatürk Airport - Sahil Yolu - Aksaray - Taksim and return
    International Terminal: follow the bus signs in the terminal.
    Taksim: The bus stop is situated in front of the Point Hotel across Divan Hotel. A few minutes walk away from the Workshop venue, the Nippon Hotel
    At the International Terminal every 30 min, five minutes before the hour and the half hour - from 3.55 till 12.55.
    At Taksim: every 30 min on the hour and half hour
    Duration: approx. 45 min to 75 min depending on traffic
    Costs: 11 TRY (one way)

    2. IETT Public Bus
    Schedule: run from 6am until midnight
    Duration: approx. 1 hr to 1,5 hr depending on traffic
    Cost for 2 rides: 6 TRL. Ticket or Istanbul Kart must be purchased beforehand.

    3. by taxi or hotel shutlle
    Duration: between 35 and 65 minutes depending on traffic
    Costs from the airport to Taksim Square, Nippon Hotel: approx. 25€
    For 40 EUR a shuttle will bring you to the Nippon Hotel. Please email the hotel to make your shuttle reservation at : or

    Sabiha Gokcen International Airport transfer

    1. Havatas Bus
    Sabiha Gökçen Airport - Kavacık-FSM Bridge - 1.Levent-Zincirlikuyu Metrobus - Dolapdere - Taksim
    Taksim - Beşiktaş - Bosphorus Bridge - Tem Access Road - Sabiha Gökçen Airport (return)
    Airport terminal: follow the bus signs
    Taksim: The bus stop is situated in front of the Point Hotel across Divan Hotel. A few minutes walk away from the Workshop venue, the Nippon Hotel
    At Terminal: every 30 minutes on the hour between 4.00am and 01:00am
    At Taksim: every 30 minutes on the half hour between 3.30am and 01:00am
    Duration: approx 80 to 110 minutes depending on traffic
    Costs: 14 TRY (one way)

    2. IETT Public Bus
    Lines: Bus E-3 travel between Sabiha Gokcen International Airport and 4.Levent Subway Station
    Duration: approx 100 to 120 minutes depending on traffic
    Costs: approx 2.5 €. Ticket or Istanbul Kart must be purchased beforehand.

    3. by taxi:
    Costs from the airport to the Taksim Square costs around 50 €
    Duration: between 50 and 90 minutes depending on traffic

    Getting around in Istanbul
    For general information, see
    If you are going to travel around the city intensively using buses, metros, ferries, funiculars, and tramways, the Istanbul Kart is a good offer. Read more here.

    Metro and Tram