Comprehensive Test Ban Treaty Organization (CTBTO)

HQ: Vienna, Austria

Focal Point: Nishy D. N. Wijewardane

Key Figures: Greenhouse gas emissions


Key figures: Waste


Executive Secretary's message

"By banning all nuclear testing, the CTBT makes an important contribution to the environment. The combined yield of the nuclear tests conducted between 1945 and 1996, when the Treaty was opened for signature,  equals one 13 kiloton Hiroshima-sized bomb exploding every 53 hours for 51 years, exacting a terrible cost on human health and the environment. In the process of watching, listening and “sniffing” the globe for signs of nuclear explosions, our monitoring network also generates large amounts of data that help scientists better understand our planet, and are applied in a wide range of fields, from atmospheric and climate science, to recording earthquakes and tracking marine mammals."

Lassina Zerbo, Executive Secretary, CTBTO


CTBTO is the international organization established to ensure the build-up of a global verification regime capable of detecting nuclear explosions underground, underwater and in the atmosphere. The regime must be operational by the time the Comprehensive Nuclear-Test-Ban Treaty (CTBT), which bans all nuclear explosions, enters into force. The verification regime consists of 337 monitoring facilities supported by an International Data Centre and on-site inspection measures in the event of a suspected nuclear test.

Experience so far

The CTBTO adopted a policy of conducting all job interviews via video-conference in June 2007, thereby saving more than 200 air trips over the past two years.

The decision to save on cooling and heating costs by keeping office buildings two degrees warmer in summer and two degrees colder in winter created some discomfort initially, but is now accepted.

Installed a green roof on one of our buildings.

Reduction efforts

CTBTO has had a consistent practice since 2007 to conduct all job interviews and increasingly internal business communications via video conference in order to reduce travel and emissions

CTBTO extended travel eligibility for Business Class to 9+ hours (from 7+) in May 2010, contributing to reduced carbon footprints.

Hotels used by CTBTO in Austria for conferences and workshop events are predominantly eco-friendly institutions.

CTBTO introduced car pooling to reduce numbers of individual road trips between HQ and CTBTO’s Gumtramsdorf Training facility to reduce emissions.

An environmentally friendly approach to building and sustaining IMS stations is what the CTBTO strives to adhere to.  To that effect, several IMS stations are powered via solar panels as opposed to diesel generators.  Our latest upgrade project to that effect is RN39, Christmas Island which is currently powered 24/7 by diesel generators.  The possibility to replace this source of power to solar is currently being evaluated.

Reduction achievements

We conducted 619 interviews and 245 interviews in 2013 and 2014 respectively for all categories of staff, avoiding significant travel. 

Staff increasingly cycle, in small numbers, to office in summer, as part of lessening car use.

Car pooling is now used daily to transfer staff between HQ and organisational facility out of Vienna (3-5 staff, 2-3 times a week, 60 km round trip).


The CTBTO has not looked into this option at this point.

Next Steps

While we don’t have an explicity environmental strategy or policy relating to our worldwide station network, there is a Monitoring Facilities Support Guideline on disposal and green acquisition strategy. Hence CTBTO pursues its green conscience.


CTBTO case studies