ASHRAE 62.1 is the U.S. standard that establishes minimum ventilation rates and procedures for acceptable indoor air quality in commercial buildings.

What it requires

It prescribes outdoor air rates per occupant and per floor area, and defines compliance paths such as the ventilation rate procedure and the indoor air quality procedure.

Where heat recovery fits

Higher required outdoor airflow means more conditioned air is exhausted. Heat recovery captures energy from that exhaust, letting you meet 62.1 without a large heating or cooling penalty.

Design tip

Common pitfall

Sizing the recovery device on total airflow rather than the outdoor-air fraction. The payback is driven by the exhaust energy you actually recover.

Bottom line

62.1 sets the ventilation need; recovery is the most cost-effective way to satisfy it in cold or hot climates.

ASHRAE Standard 84 specifies methods of testing the thermal performance of air-to-air heat exchangers and energy recovery ventilators (ERV/HRV).

Scope

It covers the apparatus, instrumentation, and calculation procedures needed to determine sensible and latent effectiveness of recovery devices under defined conditions.

What you get

A repeatable, lab-grade effectiveness number you can compare across North American manufacturers, independent of marketing claims.

Metrics reported

Relation to rating

ASHRAE 84 provides the test method; rating standards such as AHRI 1060 reference it to publish certified performance.

How to use it

Request the ASHRAE 84 test report and confirm the rating conditions match your design before accepting a quoted effectiveness.

EN 16798 is the European standard family for the energy performance of buildings - ventilation. It is the practical calculation tool for meeting the Energy Performance of Buildings Directive (EPBD).

Scope

It provides calculation methods for energy use in buildings, including thermal, internal, and HVAC loads, with dedicated modules for ventilation and air handling.

The heat-recovery link

Many national implementations of EN 16798 require mechanical ventilation systems above a defined airflow to include heat recovery with a minimum sensible effectiveness - commonly around 70-75%.

Key modules

How to apply

When designing a non-residential building in Europe, confirm the local EPBD transposition. If your AHU exceeds the threshold airflow, you must demonstrate recovery effectiveness - which is where EN 308 testing feeds in.

Common pitfall

Treating recovery as optional. Once the ventilation rate is fixed by EN 16798-1, the recovery device is what keeps the heating/cooling energy within the EPBD budget.

EN 308 is the European standard that specifies test methods for the determination of heat transfer in heat exchangers, including the air-to-air recovery devices used in HVAC. It is the foundation that lets you trust a manufacturer's effectiveness number.

What it covers

EN 308 describes the laboratory set-up, instrumentation accuracy, and calculation procedure for measuring both sensible and - where applicable - latent (moisture) transfer between the two airstreams under controlled, repeatable inlet conditions.

The core metric: effectiveness

How to read a test report

Always check the inlet temperature and humidity, the airflow rates, and whether the figure is sensible or total. A wheel quoted for total effectiveness is not comparable to a plate quoted for sensible only - EN 308 lets you normalise this.

Common pitfall

Comparing a certified EN 308 value at one airflow against a brochure value at a different airflow. Effectiveness varies with face velocity, so match the duty conditions.

Why it matters to you

Specifying against EN 308-tested values protects you from overstated performance and supports compliance with building energy rules. Pair it with the EN 13053 AHU rating for a complete specification.