ASHRAE’s Standard 62, “Ventilation for Acceptable Indoor Air Quality,” has generated a lot of controversy over the years. That controversy came to a climax when the ASHRAE board took the unprecedented step of placing the old standard (62-89) into continuous maintenance in June 1997. That meant the committee had to start back at square one, which it did in January 1998.

Thankfully, things have settled down a little since then. With the approval of four addenda in June 1999, the standard has been renamed 62-1999.

Four years ago, 62-99 was essentially divided in two, so that Standing Standard Project Committee (SSPC) 62.1 works on indoor air quality issues in commercial, institutional, and high-rise residential buildings, and SSPC 62.2 does the same in low-rise residential buildings.

Both committees operate under the consensus approach, which basically means the committee must reach consensus before taking the next step in the standard process. But the word “consensus” is debatable, as it means more than a majority but not unanimity.

If only a few people vote against it, then consensus has probably been reached. But then again, it depends on who is objecting and their reasons for doing so.



News on 62.1

The whole intention behind the new standard, says Andy Persily, chairman of SSPC 62.1, is to make life easier because it will contain clear requirements. “You’ll know whether you’ve complied or not, as opposed to the current version of 62, which is full of vague requirements and recommendations that are open to interpretation by the users, code officials, lawyers, and so on.”

To that end, the committee has been working doggedly on the many different addenda to the standard (there are far too many addenda to include here, but they are listed quarterly in the ASHRAE publication IAQ Applications). Working on the addenda means not only revising all of 62-89, but also putting the standard into “enforceable” language.

Once those two tasks are accomplished, it is ASHRAE’s hope that the standard will be adopted by code bodies more often. In fact, the society has put together a code interaction subcommittee that will focus on getting ASHRAE standards adopted more often by code authorities.

Persily says he hopes to have a full code language version of the standard by next year, although he says it may take a little longer than that.



Slow Going

As noted, 62.1 was placed into continuous maintenance and the going has been rather slow. That’s because the committee must sort through all of the existing standard and come up with addenda. The addenda then go through a number of ASHRAE committees before they are approved for public review.

After the comments are collected, the committee decides whether or not to incorporate the comments. If they are incorporated, the addenda may need to be sent out for public review again. After that, the addenda may become part of the standard, provided no one successfully appeals their approval.

The public may also submit proposals to the standard at any time, which the committee must review and vote on. As Persily notes, “Each addendum has its own separate timetable. One might be done this year, but another one might be done next year.”

Within the last year, the committee has approved one more addendum: 62p, which concerns the need to provide enough combustion air to dilute pollutants from combustion devices indoors and also addresses how to make sure equipment is properly vented.

There are also four addenda that recently went out for public review, and the committee plans to discuss the comments received at the Winter Meeting in Atlanta, GA. Persily says they will also prepare a few more addenda for public review there as well.

Persily adds that another new member has recently joined the committee, which contractors should be pleased to hear about.

“SMACNA is now an organizational member of the committee, so that’s good news for contractors. They’ll have an additional voice at the table.”



On The Residential Side: Whole-House Ventilation

Committee members of SSPC 62.2 have been busy as well. In June of this year, ASHRAE approved the recommendations from the committee and released the standard for its first public review.

Committee chairman Max Sherman met with his committee in November to review all the comments and propose responses, and they plan to spend their time at the Winter Meeting resolving additional problems.

One of the key issues of 62.2 involves whole-house ventilation, which is still rather uncommon in the United States. The standard would detail the rates required for whole-house ventilation based on the size of the house, but they will normally be within the 40- to 90-cfm range.

“The standard allows various alternatives to combine the whole-house ventilation requirement with other parts of the hvac system, such as using bathroom fans or air handlers,” says Sherman.

As for kitchen and bathroom exhaust, the committee supports exhaust fans of at least 50 cfm in all wet rooms, but there will be some exceptions to these requirements; namely:

  • Kitchens will be able to use recirculating fans when there is a window.

  • Toilets can be ventilated by their attachment to a bathroom.

  • Laundries can be ventilated by their dryer vent.

  • And bathrooms can be ventilated at lower rates if the fan operates continuously.

    • The committee has also set minimum equipment specifications for air-moving equipment. For example, sound limits will be determined so that occupants will not object to the noise.

    Central air handlers will be required to have “reasonable” particle filtration. The standard also encourages air handlers and associated ductwork to be sealed, especially when these items are located in garages.

    Sherman notes that when the standard is finished and adopted by local codes, he believes it will provide a low-cost way of providing the minimum ventilation required for acceptable indoor air quality.

    “In most cases, we would not expect a reasonable implementation of the standard to cost over $200 extra, and in some jurisdictions it may cost almost nothing. The benefits to the occupants and owners of the building, however, can be quite significant in terms of a healthier and more comfortable indoor environment.”

    Publication date: 12/06/2000