51. Acoustics. Requirements for the performance and calibration of reference sound sources used for the determination of sound power levels. (11th December 2020) Authors: British Standards Institution, Record Type: Book Extent: 1 online resource (30 pages) View Content: Available online (eLD content is only available in our Reading Rooms) ↗
52. Sampling procedures for inspection by variables. Part 1: Specification for single sampling plans indexed by acceptance quality limit (AQL) for lot-by-lot inspection for a single quality characteristic and a single AQL Part 1, (22nd August 2022) Authors: British Standards Institution, Record Type: Book Extent: 1 online resource (118 pages) View Content: Available online (eLD content is only available in our Reading Rooms) ↗
53. Heat recovery ventilators and energy recovery ventilators. Method of test for performance. Development of metrics for evaluation of energy related performance Part 1, (10th August 2022) Authors: British Standards Institution, Record Type: Book Extent: 1 online resource (50 pages) View Content: Available online (eLD content is only available in our Reading Rooms) ↗
54. Tracked Changes. Plastics. Determination of refractive index (ISO 489:2022). (23rd May 2022) Authors: British Standards Institution, Record Type: Book Extent: 1 online resource (52 pages) View Content: Available online (eLD content is only available in our Reading Rooms) ↗
55. Adjustable speed electrical power drive systems. General requirements. Rating specifications for low voltage adjustable frequency a.c. power drive systems Part 2, (15th December 1998) Authors: British Standards Institution, Record Type: Book Extent: 1 online resource (80 pages) View Content: Available online (eLD content is only available in our Reading Rooms) ↗
56. Tracked Changes. ISO general purpose metric screw threads. Tolerances. Limit deviations for screw threads Part 3, (29th March 2022) Authors: British Standards Institution, Record Type: Book Extent: 1 online resource (104 pages) View Content: Available online (eLD content is only available in our Reading Rooms) ↗
57. Plastics. Determination of refractive index (ISO 489:2022). (10th May 2022) Authors: British Standards Institution, Record Type: Book Extent: 1 online resource (20 pages) View Content: Available online (eLD content is only available in our Reading Rooms) ↗
58. BS ISO 16494-1 AMD 1. Heat recovery ventilators and energy recovery ventilators. Method of test for performance. Part 1. Development of metrics for evaluation of energy related performance (28th February 2023) Authors: British Standards Institution, Record Type: Book Extent: 1 online resource (15 pages) View Content: Available online (eLD content is only available in our Reading Rooms) ↗
59. Tracked Changes. Hydrometric uncertainty guidance (HUG). (7th March 2023) Authors: British Standards Institution, Record Type: Book Extent: 1 online resource (196 pages) View Content: Available online (eLD content is only available in our Reading Rooms) ↗
60. Acoustics. Measurement of airborne sound emitted by vessels on inland waterways and harbours. (5th January 2021) Authors: British Standards Institution, Record Type: Book Extent: 1 online resource (20 pages) View Content: Available online (eLD content is only available in our Reading Rooms) ↗