{"id":17104,"date":"2026-03-24T12:06:19","date_gmt":"2026-03-24T19:06:19","guid":{"rendered":"https:\/\/dev.withbureau.com\/?post_type=glossary&#038;p=17104"},"modified":"2026-04-01T20:05:59","modified_gmt":"2026-04-02T03:05:59","slug":"iso-23351","status":"publish","type":"glossary","link":"https:\/\/withbureau.com\/uk\/glossary\/iso-23351\/","title":{"rendered":"ISO 23351"},"content":{"rendered":"\n<p class=\"has-black-color has-text-color has-link-color wp-elements-c8ff761e4b9d433e297a3edf85bdccc1\">ISO 23351 is an international standard for measuring speech reduction in enclosed, furniture-like workspaces such as office booths. It evaluates acoustic performance under real-world conditions, accounting for factors like openings, ventilation, and installation environments, making it more relevant than traditional wall-based metrics for assessing speech privacy.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Why ISO 23351 Matters for Modern Acoustic Spaces<\/h2>\n\n\n\n<p class=\"has-black-color has-text-color has-link-color wp-elements-98a1a7ce24357b848229cecefb54affb\">ISO 23351 was developed to address a gap in how acoustic performance is measured in modern work environments. Traditional metrics were designed for sealed walls and controlled laboratory conditions, which do not reflect how enclosed, furniture-like spaces actually function. Office booths and similar environments include ventilation, openings, and real-world installation variables that significantly influence how sound behaves.<\/p>\n\n\n\n<p class=\"has-black-color has-text-color has-link-color wp-elements-22eb12ab5037c6dcc4992f259c4758d0\">This standard focuses specifically on measuring speech reduction in conditions that mirror everyday use. By doing so, it provides a more accurate understanding of how much conversation is reduced as it leaves a space, which is directly tied to speech privacy and overall usability. Rather than relying on idealized testing scenarios, ISO 23351 captures the combined impact of design, structure, and airflow on acoustic performance. This makes it a more practical benchmark for evaluating enclosed workspaces, helping set clearer expectations around how they perform in real environments. By aligning testing with actual use, it shifts the focus toward outcomes that matter, such as reduced distractions, improved focus, and greater confidence in conversational privacy.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Related Terms<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><a href=\"https:\/\/withbureau.com\/glossary\/speech-reduction\/\" type=\"glossary\" id=\"17258\">Speech Reduction<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/withbureau.com\/glossary\/speech-privacy\/\" type=\"glossary\" id=\"17103\">Speech Privacy<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/withbureau.com\/glossary\/sound-transmission-class\/\" type=\"glossary\" id=\"17099\">Sound Transmission Class (STC)<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/withbureau.com\/glossary\/noise-flanking\/\" type=\"glossary\" id=\"17098\">Noise Flanking<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/withbureau.com\/glossary\/active-ventilation\/\" type=\"glossary\" id=\"17261\">Active Ventilation<\/a><\/li>\n<\/ul>\n\n\n\t<section class=\"bureau-featured-resources\">\n\n\t\t\t\t\t<h2 class=\"bureau-featured-resources__heading\">\n\t\t\t\tFeatured Resources\t\t\t<\/h2>\n\t\t\n\t\t<div class=\"bureau-featured-resources__grid bureau-featured-resources--3col\">\n\t\t\t\n\t\t\t\t\t\t\t<a class=\"bureau-featured-resources__card\" href=\"https:\/\/withbureau.com\/blog\/new\/top-office-furniture-solutions-that-block-noise\/\">\n\t\t\t\n\t\t\t\t\t<div class=\"bureau-featured-resources__image\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<img\n\t\t\t\t\t\t\t\tsrc=\"https:\/\/withbureau.com\/wp-content\/uploads\/2026\/04\/NYC_Office-One-Meet.png\"\n\t\t\t\t\t\t\t\talt=\"Silence at Work: Top Office Furniture Solutions That Block Noise\"\n\t\t\t\t\t\t\t\tloading=\"lazy\"\n\t\t\t\t\t\t\t\/>\n\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\n\t\t\t\t\t<div class=\"bureau-featured-resources__body\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<h3 class=\"bureau-featured-resources__title\">Silence at Work: Top Office Furniture Solutions That Block Noise<\/h3>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<p class=\"bureau-featured-resources__excerpt\">Anyone who has worked in an open office floor plan can tell you that noise is one of the biggest challenges in these spaces. Without the benefit of walls, these offices are filled with the sounds of people at work, including conversations, phone calls, message notifications, music, typing, and so much more. While it may feel like the cost of &#8230; \nRead More<\/p>\n\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"bureau-featured-resources__arrow\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t<svg width=\"20\" height=\"20\" viewBox=\"0 0 20 20\" fill=\"none\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\">\n\t\t\t\t\t\t\t\t<path d=\"M4.167 10h11.666M10 4.167 15.833 10 10 15.833\" stroke=\"currentColor\" stroke-width=\"1.667\" stroke-linecap=\"round\" stroke-linejoin=\"round\"\/>\n\t\t\t\t\t\t\t<\/svg>\n\t\t\t\t\t\t<\/span>\n\t\t\t\t\t<\/div>\n\n\t\t\t<\/a>\n\t\t\t\n\t\t\t\t\t\t\t<a class=\"bureau-featured-resources__card\" href=\"https:\/\/withbureau.com\/blog\/featured\/works-with-well\/\">\n\t\t\t\n\t\t\t\t\t<div class=\"bureau-featured-resources__image\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<img\n\t\t\t\t\t\t\t\tsrc=\"https:\/\/withbureau.com\/wp-content\/uploads\/2026\/03\/Bureau-Works-with-Well-1.png\"\n\t\t\t\t\t\t\t\talt=\"A New Global Standard: Bureau is the First Soundproof Booth Company to Earn \u2018Works with WELL\u2019\"\n\t\t\t\t\t\t\t\tloading=\"lazy\"\n\t\t\t\t\t\t\t\/>\n\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\n\t\t\t\t\t<div class=\"bureau-featured-resources__body\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<h3 class=\"bureau-featured-resources__title\">A New Global Standard: Bureau is the First Soundproof Booth Company to Earn \u2018Works with WELL\u2019<\/h3>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<p class=\"bureau-featured-resources__excerpt\">The workplace industry just reached a turning point. Bureau is proud to announce that we are the first and only soundproof booth company in the world to earn the Works with WELL licensing. In an era where employee well-being is directly tied to organizational success, the materials we surround ourselves with matter. While many claim to prioritize health, Bureau has &#8230; \nRead More<\/p>\n\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"bureau-featured-resources__arrow\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t<svg width=\"20\" height=\"20\" viewBox=\"0 0 20 20\" fill=\"none\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\">\n\t\t\t\t\t\t\t\t<path d=\"M4.167 10h11.666M10 4.167 15.833 10 10 15.833\" stroke=\"currentColor\" stroke-width=\"1.667\" stroke-linecap=\"round\" stroke-linejoin=\"round\"\/>\n\t\t\t\t\t\t\t<\/svg>\n\t\t\t\t\t\t<\/span>\n\t\t\t\t\t<\/div>\n\n\t\t\t<\/a>\n\t\t\t\n\t\t\t\t\t\t\t<a class=\"bureau-featured-resources__card\" href=\"https:\/\/withbureau.com\/blog\/tips\/where-to-place-a-soundproof-office-booth\/\">\n\t\t\t\n\t\t\t\t\t<div class=\"bureau-featured-resources__image\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<img\n\t\t\t\t\t\t\t\tsrc=\"https:\/\/withbureau.com\/wp-content\/uploads\/2025\/11\/Render.webp\"\n\t\t\t\t\t\t\t\talt=\"Where Should You Place a Soundproof Office Booth?\"\n\t\t\t\t\t\t\t\tloading=\"lazy\"\n\t\t\t\t\t\t\t\/>\n\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\n\t\t\t\t\t<div class=\"bureau-featured-resources__body\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t<h3 class=\"bureau-featured-resources__title\">Where Should You Place a Soundproof Office Booth?<\/h3>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<p class=\"bureau-featured-resources__excerpt\">You\u2019ve picked the perfect booth. Now it\u2019s time to make the most of it. One thing we\u2019ve learned over time is that where you place your booth can make a huge difference. It\u2019s not just about finding a spare corner. It\u2019s about choosing a spot that makes the booth easy to use, acoustically effective, and naturally integrated into the rhythm &#8230; \nRead More<\/p>\n\t\t\t\t\t\t\t\t\t\t\t\t<span class=\"bureau-featured-resources__arrow\" aria-hidden=\"true\">\n\t\t\t\t\t\t\t<svg width=\"20\" height=\"20\" viewBox=\"0 0 20 20\" fill=\"none\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\">\n\t\t\t\t\t\t\t\t<path d=\"M4.167 10h11.666M10 4.167 15.833 10 10 15.833\" stroke=\"currentColor\" stroke-width=\"1.667\" stroke-linecap=\"round\" stroke-linejoin=\"round\"\/>\n\t\t\t\t\t\t\t<\/svg>\n\t\t\t\t\t\t<\/span>\n\t\t\t\t\t<\/div>\n\n\t\t\t<\/a>\n\t\t\t\t\t<\/div>\n\n\t<\/section>\n\t","protected":false},"excerpt":{"rendered":"<p>ISO 23351 is an international standard for measuring speech reduction in enclosed, furniture-like workspaces such as office booths. It evaluates acoustic performance under real-world conditions, accounting for factors like openings, ventilation, and installation environments, making it more relevant than traditional wall-based metrics for assessing speech privacy. Why ISO 23351 Matters for Modern Acoustic Spaces ISO 23351 was developed to address &#8230; <\/p>\n<div><a href=\"https:\/\/withbureau.com\/uk\/glossary\/iso-23351\/\" class=\"more-link\">Read More<\/a><\/div>\n","protected":false},"featured_media":0,"template":"","glossary_category":[],"class_list":["post-17104","glossary","type-glossary","status-publish","hentry","no-post-thumbnail"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.6 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>What is ISO 23351 - Bureau<\/title>\n<meta name=\"description\" content=\"Learn what ISO 23351 measures, how it evaluates speech reduction in real-world conditions, and why it\u2019s more relevant than traditional acoustic metrics for booths.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/withbureau.com\/uk\/glossary\/iso-23351\/\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:title\" content=\"What is ISO 23351 - 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