ISO_NWIPs-for-Ballot

ISO/NP

460 461

5.2 Installation conditions and safety

5.2.1 Installation room 5.2.1.1 Size 462 The installation room shall be large enough to provide the space required for the installation and 463 operation of the apparatus, as well as the space needed to manage any stray magnetic field. 464 Furthermore, if it is not possible to reserve a control zone outside the room, the room shall be large 465 enough to completely contain the stray magnetic field of the superconducting magnet within the 466 specified values. 467 NOTE The magnitude of the stray magnetic field differs according to the magnet size and type and distance from 468 the magnetic solenoid/core. Stray field affects all directions and impacts upper and lower rooms as well as 469 adjacent horizontally. 470 5.2.1.2 Ceiling height 471 The room shall have a specified minimum ceiling height in order to perform tasks such as installing the 472 apparatus and refilling the helium tanks. 473 NOTE The required height differs according to the magnet size and type. 474 5.2.1.3 Floor 475 A floor that is not subjected to any significant vibration is preferred. The floor shall also satisfy the 476 specified loading and strength requirements. 477 5.2.2 Air conditioning and ventilation facilities 478 The NMR apparatus should be installed in an air-conditioned room. 479 When the superconducting magnet is installed, several cubic metres of helium and nitrogen gas will be 480 released inside the room. To prevent oxygen deficiency in the room, exhaust fans with suitable 481 ventilation capacity and performance shall be installed. These fans should be selected in accordance 482 with the installation instructions for the NMR apparatus. 483 Furthermore, if the magnetic field is accidentally disrupted or quenched, a large amount of helium gas 484 and nitrogen gas will be released from the superconducting magnet. For this reason, quench ducts to 485 the exhaust ports of the superconducting magnet may need to be installed (See Figure 2). Safety 486 measures should be taken to appropriately handle this release of gas, such as equipping the room with 487 an oxygen concentration meter and adequate ventilation fans. 488 Typical installation conditions for a general 400 MHz NMR apparatus are 489 floor vibration of ≤0,2 cm/s 2 (Gal), 490 floor strength to withstand a load of ≥600 kg,/m 2 491 air temperature range from 17 °C to 27 °C (fluctuation within ±1 °C/h), and 492 relative humidity ≤70 % (see Figure 1). 493 NOTE1 Since the NMR apparatus utilizes a superconducting magnet, warning indications about the strong 494 magnet fields generated should be posted at the entrance to the room and on the superconducting magnet, and 495 unauthorized persons shall not be allowed to enter the room. 496

© ISO 2017 – All rights reserved

17