History: TNO-PML at Rijswijk and Ypenburg


The history of TNO Defence research at Rijswijk and Ypenburg


The origin

In 1838, chemical and ballistic laboratory research for the Dutch Defence started at the Chemical Laboratory in Delft. The Chemical Laboratory belonged to the Pyrotechnische Werkplaats (Pyrotechnical workshop), also located near the Paardenmarkt, Delft. With several other facilities, these workshops will later officially become ‘Artillery Establishments‘ (in Dutch: Artillerie Inrichtingen), a name that was already in use at that time. The work of the laboratory will have been in agreement with what will later become the core of technological-chemical defence research for some time: the characterisation and testing of substances, materials and ammunition components such as igniters, percussion caps, and gunpowder. Systematic research, aimed at improving production processes and thus improving technology – would not have been the order of the day. If performed, it would still have a predominantly empirical character.

After 1880, it became clear that the location in Delft was not suitable for the expansion of the company that was deemed necessary. The eye then falls on a new, spacious site on the Hemveld near Zaandam. In 1895, the construction of the Artillery Establishments started. At the turn of the century, the relocation took place. The Delft residents regard the move as an emigration; the Chemical Laboratory is also moving together with the warehouses and workplaces. Although the employees are not too happy with their less pleasant new living environment, the new location is excellent from a technical point of view: good transport by water and rail, and sufficient expansion possibilities. Moreover, there is no urban development in the immediate vicinity that can be at risk in the event of an industrial accident.

The First World War gave new impetus to research. The Chemical Armament Commission was established per a secret decision. At the Ministry of Defence, it is not just about increased demand for the usual activities. Attention is paid to a completely new facet of modern warfare: the use of chemical weapons such as phosgene and mustard gas. In the Netherlands, this leads to purchases of protective equipment, primarily gas masks. Initially, these were manufactured and procured in England. Later, the Artillery Establishments ensured production in the homeland. Disinfection research is also performed. This requires the production of small quantities of combat gases for testing purposes.

In the 1930s, the newly formed Defence advisory committee on the topic of battle gases naturally appealed to Ir. A.J. der Weduwen -the head of the Chemical Laboratory- to join the committee as secretary.
As part of the preparations for a possible war, the Central Laboratory of the General Headquarters of the General Staff was set up in 1939 with special responsibility for research into the ‘chemical threat’. This is led by the “Committee on Chemical and Related Warfare Products”. Close cooperation with the more materially oriented Chemical Laboratory was a priority.
In the meantime, a second branch of the Artillery Establishments for Ammunition Manufacturing is established at the Lange Kleiweg in Rijswijk. In 1939, the Chemical Laboratory returned to Delft. It was housed with a staff of around 15 employees in the Chemical Technology building of the Technical University, Poortlandlaan (Julianalaan) 134, Delft.

Julianalaan 134, Delft
Poortlandlaan (now Julianalaan) 134, Delft


WW II and the German occupation

Immediately after the fall of the Grebbelinie on May 14, 1940, management decided to either destroy or hide in safety the research archives. On the same day, the archive is transported to London with the ship ‘Scheveningen VI’. Dr. P.A. Jonquière remains in Leiden. He is given charge of the laboratory and has to handle current affairs. 

On British soil, work is being continued under the name of ‘Central Laboratory, London Department’ under the supervision of the Dutch authorities. In a material sense, the Laboratory comes under the umbrella of the British Ministry of Supply, which provides the necessary facilities.
This ‘English period’ will be of guiding significance for the later chemical warfare research program in the Netherlands. Not only because their work could be continued during the war years, but also by participating in the meetings of the interallied Chemical Board. A great deal of knowledge and experience is gained from the investigations by the Allies. Moreover, fruitful personal contacts were established in those years. After the war, this greatly facilitated international cooperation. Attention is paid to the threat of more or less well-known agents such as blue acid, chlorine cyan, phosgene, mustard gas, cadmium and arsenic compounds. This results in research in the field of detection, disinfection, protective clothing and gas masks.

Interlude: Since its foundation in 1937, TNO had the intention to have its own laboratories. During the German occupation, TNO received about a half site at the Lange Kleiweg in Rijswijk that had been in use by the Artillery Establishments. The Department of Finance cooperated by paying the purchase price in four annual instalments of NLG 50,000. Moreover, as a matter of urgency, five (modest) laboratories were set up for the Central Institute for Materials Research at that site.

During the German occupation, the (Queen) Julianalaan, Delft was renamed to Poortlandlaan. Directly after the German invasion in 1940, the  Chemical Laboratory started research on agriculture: chemical analysis on dried grass, starch, straw, peat, and the like. Work of importance… In this way, the laboratory managed to continue under the German occupation without much damage. The earlier defence-related activities of the Artillery Establishments came to a halt for obvious reasons. The workforce converts shop to the manufacturing of agricultural machinery. In 1943, three years after the German occupation of The Netherlands, the Chemical laboratory is bought by the TNO Central Organisation (as can be found in a post-war report) as ‘T.N.O. Laboratorium Poortlandlaan’. 

After the Second World War

Directly after the war, a strong tendency exists to bundle scientific research for defence and to take a different approach from the pre-war years. It appears that the Netherlands Organisation for Applied Scientific Research TNO is an excellent framework for accommodating this research area. On July 6, 1946, the government approved the plan for a special organisation under the Central Organisation of TNO in which natural science research for the Netherlands defence could be bundled with a legal entity with a public-law character. On July 12, 1947, the National Defence Organisation (RVO-TNO) was established with its registered office in The Hague. The chairman is Prof. Dr. G.J. Sizoo. RVO-TNO also host the Chemical Laboratory of the Artillery Establishments, which then continues as the Technological Laboratory RVO-TNO. Ir. AJ der Weduwen becomes the director. He also acted as secretary to the National Defence Organisation’s Board during its start-up phase.
The more or less related Central Laboratory of the Armed Forces becomes the Chemical Laboratory RVO-TNO. Own housing is not yet available; both the Technological and the Chemical Laboratories will remain ‘in rooms’ of the Technical University Delft at the Julianalaan 134 for a long time.

The technology research activities from before the war are resumed: test work for the Armed Forces, covering more fields than just the field of explosives. Research is also being conducted on all kinds of other materials that are used by the Armed Forces, such as oils, waxes, and lubricants. Contact with the Technical University Delft, which will later be represented in the so-called Assistance Committee, is an important support to this work.

Along the Lange Kleiweg, Rijswijk, on a well-known terrain (see above), an own TNO research complex is being built for both laboratories mentioned above, and for the Medical Biological Institute (MBI) which was based in Leiden.

PML Lange Kleiweg, Rijswijk
PML, Lange Kleiweg, Rijswijk

The MBI, founded in 1947, became the Medical-Biological Laboratory (MBL) in 1952. The MBL applied pharmacological, molecular-biological and biophysical research in an integrated manner for the understanding of the molecular processes in the nervous system and the immune system. The MBL also investigated genetic material (DNA). With this knowledge, the Ministry of Defence worked on the one hand on protection against radioactive, chemical and biological weapons, and on the other hand on the treatment of the effects of these weapons such as nerve gas poisoning.
On 29 January 1954, HRH Prince Bernhard opens the new Medical-Biological Laboratory (MBL) at the Lange Kleiweg 137, Rijswijk. The MBL is part of the National Defence Research Organisation TNO until 1 April 1977.

Opening of the MBL by HRH Prince Bernhard on 29/01/1954
Opening of the MBL by HRH Prince Bernhard on 29/01/1954
Explanation of on-going research
Explanations of ongoing research at the MBL 

In 1956, the Technological Laboratory moved into the new housing “Prince Maurits Building”, adjacent to the MBL. The Chemical Laboratory followed in 1957. The opening of the new building of both institutes took place by the Minister of Defence on April 17, 1957.


Relief designed by prof.dr. O. Wenckenbach depicting Prince Maurits and Simon Stevin. In the background pentagonal bastions, a sailing wagon, 'Wisconstighe Ghedachtenissen' (mathematical deliberations), hydraulic engineering (mill), the balance law for levers and the 'clootcrans'. The relief is loacted in the main lobby of the Prince Maurits Lab building at the Lange Kleiweg, Rijswijk.
Relief designed by Prof. Dr. O. Wenckenbach depicts Prince Maurits and Simon Stevin. In the background pentagonal bastions, a sailing wagon, ‘Wisconstighe Ghedachtenissen’ (mathematical deliberations), hydraulic engineering (mill), the balance law for levers and the ‘clootcrans’. The relief is located in the main lobby of the Prince Maurits Lab building at the Lange Kleiweg, Rijswijk.


TNO location Plaspoelpolder, Lange Kleiweg, Rijswijk
TNO location Plaspoelpolder, Lange Kleiweg, Rijswijk

Even then, the main laboratory rooms of the Technological Laboratory are those for powder testing and chemical analysis. For working with extremely sensitive substances, such as silver azide, for that matter, grateful use is made of the old Artillery Establishment buildings that were left from the past and were already equipped for working with explosive substances.
A further specialisation is gradually coming about. For example, a separate laboratory for explosion protection is set up.

In the early sixties, rocket engine research started under the supervision of the later director Dr. E.W. Lindeijer. Research into the functioning of ammunition increasingly become a daily routine. At the same time, the Armed Forces ask TNO to contribute to the further development of munitions or components thereof to assist the Dutch industry, such as Eurometaal Zaandam or MuidenChemie. In turn, this is an incentive to study explosive processes more fundamentally. Ultrafast photography and X-ray flash are introduced in that context; new research bunkers are being built. In addition, the institute also has an educational function: Giving courses to train ammunition officers of the Armed Forces.

From 1969 onwards, the laboratory was closely involved in the UN disarmament talks on chemical warfare. In addition, the available expertise is used for military labour and environmental hygiene, battery research, and civilian topics.

In the seventies, Dr. E.W. Lindeijer was succeeded by Dr. Ir. H.J. Pasman as director of the Technical Laboratory. He changes the character of the work from chemical to mainly physical. It already starts with the gunpowder inspection, where research into a new method of research based on a sensitive measurement of heat development starts to bear fruit. Gradually the effects of explosive reactions will become the main subject: internal and end ballistics and ‘blast’ research using ‘blast’ simulators.
At the same time, the technology for the production of explosive charges is renewed. Not only the Armed Forces benefit from this research in explosions. An important civilian spin-off is the explosion safety work mainly commissioned by the Dutch process industry and by government bodies responsible for the safety of the production, transport, and storage of explosion-sensitive substances.
The work of the Chemical Laboratory shifts its focus more on protection measures.

In the second half of the seventies, the experimental facilities of the Technological Laboratory were increasingly supplemented by the development of computer models. Ballistic codes and flow models contribute to broadening insight into complex, high-speed processes. The computer is an absolute condition for this and other work. The now-familiar computer screens appear in many places in the laboratory.
Vulnerability analysis becomes possible and the effects of weapons and ammunition against targets can be evaluated. With a relatively small group of people, vulnerability to a spectrum of threats to various flying, sailing and vehicles is determined.

The TNO Prins Maurits Laboratory

On 1 January 1979, the Chemical Laboratory TNO and the Technological Laboratory TNO merged: the TNO Prince Maurits Laboratory (TNO-PML) was established. The same building houses a third institute, the Medical Biological Laboratory TNO (MBL), which originally also belonged to the RVO (TNO Defence Organisation). In 1978, however, the MBL was transferred to the TNO Health organisation. The collaboration between PML and MBL remains close.

TNO-PML, Lange Kleiweg 137, Rijswijk
TNO Prins Maurits Laboratory, Lange Kleiweg 137, Rijswijk

In the period 1980-1985, the system analytical approach to weapon-target interactions greatly improved the understanding of the key weapon parameters that largely determine the outcome of a combat. The research also allows contributing internationally to new developments in ammunition and guided projectiles.
On a national basis, this type of activity is considered to be too expensive, except for the Goalkeeper near-defence system for the Royal Netherlands Navy, proximity pipes, and some explosive cartridge developments for which building blocks have been supplied.

From 1985 onwards, the Ministry of Defence encouraged technological development work by the private sector, among other things enterprises to be better prepared for product development, cooperatives and co-productions in an international context. The Technological Research side of TNO-PML assists enterprises with specialist assistance and research facilities for the technological development of light armour materials and plastic-bound explosive materials.

In 1988, the Prince Maurits Laboratory celebrated several anniversaries simultaneously: 150 years of defence research, 40 years of the Chemical and Technological Laboratories, and 10 years of Prince Maurits Laboratory. The following research groups are at that time active within the institute:

  • Analytical Chemistry
  • Organic Chemistry and Biochemistry
  • Protection and Risk Analysis
  • Ammunition functioning and Explosive materials
  • Ballistics and Rocket technique
  • Weapon effects
  • Pulse Physics
  • Explosion Safety

Name changes

Like the other special organisations of TNO, the TNO Defence Organisation was dissolved in a reorganisation in 1980. The function moves to the new TNO Defence Research. On December 31, 2005, TNO decided to dissolve the individual TNO institutes (laboratories). The TNO-PML institute is absorbed in the new TNO core area TNO Defence and Security (TNO DV). Subsequently, the TNO core area structure was dissolved on 1 January 2011. TNO is transformed into a single TNO entity. Since then, the Rijswijk Plaspoelder and The Hague-Ypenburg locations, which work alongside the Den Haag Waalsdorp and Soesterberg locations, have been working for the Defence, Safety and Security (DSS) unit.
In the fall of 2018 and the spring of 2019, a large part of the Defence and Security work moved from the Lange Kleiweg in Rijswijk to newly built facilities at Ypenburg. On 23 May 2019, the Minister of Defense mw. Bijleveld-Schouten officially opens those new facilities for the Energetic Materials and Explosives, Ballistics and Protection research groups.

TNO location The Hague-Ypenburg
TNO location The Hague- Ypenburg


Turn and tilt table for precise shooting on armoured cars at TNO The Hague-Ypenburg (photo (c)TNO)


Opening TNO The Hague-Ypenburg by the Minister of Defence on 23 May 2019


  • H.J. Pasman (1988), “150 jaar technologische research -In vogelvlucht-” en
    H. Zelm “40 jaar chemisch defensieonderzoek in Nederland” in: “Prins Maurits Laboratorium TNO: Veelzijdig en Dynamisch“, Redactie: Th.M. Groothuizen
  • Een kwarteeuw TNO 1932-1957, Gedenkboek bij de voltooiing van de eerste 25 jaar werkzaamheid van de organisatie TNO op 1 mei 1957
  • T.N.O.-Laboratorium Poortlandlaan – Verslag omtrent de lotgevallen van het Scheikundig Laboratorium der Artillerie-Inrichtingen gedurende de Duitsche bezetting (ca. 1945)