div class=ts-pagebutton class=gotoPage data-page=1Page 1button div class=ts-imageimg data-url=british-standards-for-arp-requirementshtmlpage=1 data-page=1 class=ts-thumb lazyload alt=Page 1: British Standards for ARP Requirements loading=lazy src=data:imagegifbase64iVBORw0KGgoAAAANSUhEUgAAAAIAAAACCAQAAADYv8WvAAAAD0lEQVR42mP8X8AwAgiABKBAv+vAXklAAAAAElFTkSuQmCC data-src=https:reader038vdocumentsmxreader038viewer2022100510575067df1a28ab0f07ad8a80html5thumbnails1jpg width=140 height=200 divp© 1939 Nature Publishing Grouppdiv