{"id":30814,"date":"2024-05-07T11:41:15","date_gmt":"2024-05-07T03:41:15","guid":{"rendered":"https:\/\/smartairfilters.com\/?p=30814"},"modified":"2025-01-09T06:33:16","modified_gmt":"2025-01-08T22:33:16","slug":"ashrae-per-hour-office-residential-school-virus","status":"publish","type":"post","link":"https:\/\/smartairfilters.com\/en\/blog\/ashrae-per-hour-office-residential-school-virus\/","title":{"rendered":"ASHRAE Recommended Air Changes Per Hour"},"content":{"rendered":"

Data shows that improving indoor ventilation can reduce the risk of virus transmission<\/a>, and is recommended by the CDC<\/a>.  But what are the recommended air changes per hour for different spaces? In this article, we\u2019ll cover the recommended ASHRAE recommended air changes per hour for offices, homes, schools, residential and hospitals, using the ASHRAE 62.1 and 62.2 guidelines.<\/p>\n\n\n\n

ASHRAE Recommended Air Changes Per Hour<\/h2>\n\n\n\n

In the US, ASHRAE sets the minimum outdoor air ventilation rates for buildings in the ASNI\/ASHRAE Standard 62.1 and 62.2 guidelines. These standards specify how much\u00a0outdoor\u00a0<\/strong>air should be brought into a room every hour, and are based on occupancy and room size.<\/p>\n\n\n\n

Read More: What is Air Changes Per Hour (ACH) & How to Calculate<\/a><\/p>\n\n\n

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\"ASHARE<\/figure><\/div>\n\n\n

The ASHRAE 62.1 (\u201cVentilation and Acceptable Indoor Air Quality in Residential Buildings\u201d) recommends homes receive no less than 0.35 air changes per hour of outdoor air to ensure adequate indoor air.<\/p>\n\n\n\n

For other spaces like offices, shops, and schools, the ASHRAE 62.1 standard doesn\u2019t give a fixed number. Instead, airflow rates based on the size of a room, its use (e.g. school, office, sports arena) and the number of people inside are provided. These can be used to calculate exact airflow requirements for a certain space.<\/p>\n\n\n\n

The table below provides a summary of the ASHRAE recommended air changes per hour for common building types. These air changes per hour are based on typical room sizes and occupancy rates, including for homes, hotel rooms, offices, schools and shops.<\/p>\n\n\n

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\"Recommended<\/figure><\/div>\n\n\n

Learn More: Air Purifiers & COVID-19 Protection for Schools \u00bb<\/a><\/p>\n\n\n\n

The table above gives approximate air changes per hour for schools, homes, hotels, shops, and restaurants. Exact ventilation rates for a given space should be calculated based on the ASHRAE 62.1 standard. But the rules below are helpful starting points for calculating the recommended air changes per hour for your space.<\/p>\n\n\n\n

Doubling Room Occupancy Means Doubling Air Changes Per Hour<\/h3>\n\n\n\n

Ventilation and air change rates are calculated on a per-person basis. If the number of occupants in a room doubles, the required ventilation rate or air change doubles. This rule can be useful for office spaces as the occupancy level changes.<\/p>\n\n\n

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\"Doubling<\/figure><\/div>\n\n\n

Bigger Spaces Require More Outdoor Air<\/h3>\n\n\n\n

This rule is simple. Ignoring the number of people in a room, a room that\u2019s 100sqm requires twice as much outdoor air as a room that\u2019s 50sqm.<\/p>\n\n\n\n

When Should the ASHRAE Standard Not be Used?\u00a0<\/h2>\n\n\n\n

The ASHRAE Standard is a useful guideline for ventilation and air change rates in homes, offices hospitals and classrooms. However, there may be some situations where the recommended ventilation rate here is too low. The ASHRAE Standard outlines two of these situations:<\/p>\n\n\n\n