ASHRAE 189.1-2009 Overview
SKIP TO:
Light Pollution Reduction: (as specified in Section 5.3.3 of the Standard)
- General - show compliance with ASHRAE 90.1-2007 + addendum i + addendum br
- Uplight - two options:
- meet the allowable uplight rating (per the BUG rating system) based on the appropriate lighting zone using table 5.3.3.2A of the Standard, OR
- meet the threshold for uplight as a percentage of total emitted light using table 5.3.3.3 of the Standard
- Glare:
- for building mounted luminaires within 2 mounting heights of any property line, meet the glare ratings specified in Table 5.3.3.2B of the Standard
- for all other luminaires, meet the glare ratings specified in Table 5.3.3.2A of the Standard
- Backlight - meet the backlight ratings specified in Table 5.3.3.2A of the Standard
Lighting Energy: (as specified in section 7.4.6 of the Standard)
- General - show compliance with ASHRAE 90.1-2007 plus the following
- Lighting Power Allowance - the interior lighting power allowance in 189.1-2009 is specifed as 90% of that allowed in 90.1-2007
- Occupancy Sensors:
- section 7.4.6.2 of the Standard prescribes where occupancy sensors are required and how they must operate, and
- section 7.4.6.3 prescribes the use of multi-level occupancy sensors in other space types
- Egress & Security Lighting - 189.1 sets a limit on the LPD of any lighting that is on 24/7 for reasons of security or egress; more may be used but the additional lighting must be on auto shutoff
- Daylight Harvesting - Electric lighting must be reduced in response to available daylight either by
Continuous daylight dimming OR a combination of stepped switching and daylight-sensing automatic controls - "Manual On" Occ Sensors - section 7.4.6.6 says that all occ sensors, except for those mandated by section 7.4.6.3 described previously, must be auto-off/manual-on but this seems to be a contradiction to 7.4.6.2 where it says auto on to a lower light level is allowed.
- Exterior Lighting Controls:
- First the requirements of 90.1 must be met … THEN …
- For certain area types, the total lighting power must be reduced by at least 50% one hour after normal closing and completely turned off within 30 minutes after sunrise.
- Hotel/Motel Guest Rooms - in section 7.4.3.12 of the Standard, it states that all lighting and switched outlets must be automatically switched off whenever the guest room is unoccupied if the facility has over 50 guest rooms.
- Reach-in Refrigerator/Freezer Display Cases - section 7.4.7.4 of the Standard sets a limit on lighting loads for reach-in refrigerators and freezers.
- If they have case doors over 5’ in height, they are allowed 46 watts per door.
- Otherwise they are allowed only 42 watts per door
- Energy Consumption Management - per section 7.3.3 of the Standard:
- 189.1 also requires that energy consumption be measured and remotely communicated for any energy source type exceeding the specified thresholds.
- When any of those thresholds are exceeded and then any of the subsystem thresholds of the lower table are exceeded, that individual subsystems must be measured separately.
- So, e.g., if a building uses over 200 kVA electrical service and the lighting load accounts for more than 50 kVA, then the lighting must be separately measured.
Daylighting
- Minimum Fenestration by Toplighting - not including certain exceptions, per section 8.3.4 of the Standard, certain large enclosed spaces must meet the following minimum toplighting requirements. These spaces include (within buildings that are 3 stories or less above grade) any enclosed space that is greater than 20,000 sq.ft, is under a roof with a finished ceiling greater than 15’ in height and has an LPD allowance greater than 0.5 watts/sq.ft .
- Minimum Daylight Zone - At least 50% of the floor area must be in the daylight zone, and
- Minimum Toplighting area to Daylight Zone area ratio - the area of the toplighting compared to the area of the daylighting zone by toplighting must exceed the percentage specified in Table 8.3.4.1 of the Standard.
- Daylighting by Sidelighting - (see section 8.4.1 of the Standard)
- Minimum Effective Aperture - other than for certain exceptions, office spaces and classrooms have two sidelighting related requirements:
- All north, south and east facing facades shall have a minimum effective aperture AND
- Opaque interior surfaces in daylighted zones shall have certain minimum reflectances
- Office Space Shading - this section requires that west, south and east facing facades must have minimum level of either an external or an internal projection factor.
- Performance Option - (see section 8.5.1 of the Standard) - as with the other chapters, the performance option may be used as an alternative to the prescriptive path. For daylighting, this means running a daylighting simulation.
- Usable Illuminance in Office Spaces and Classrooms - based on certain parameters, this simulation must show that the daylighting will provide at least 30 fc over at least 75% of the daylight zone on a plane 3 feet above the floor. There is an exception for spaces where external obstructions preclude meeting this requirement
- Direct Sun Limitation on Worksurfaces in Offices - the second requirement of the daylighting simulation is demonstrating that the work surfaces are properly protected against too much direct illumination from the sun. This means that direct sunlight may not strike anywhere on a work surface in a daylighted space for more than 20% of the occupied hours on the equinox.
Use of Energy Star Equipment - section 7.4.7.3 of the Standard requires that when specified equipment falls within the scope of certain Energy Star programs, then the installed equipemnt is to comply with criteria equivalent to those in the Energy Star program. For lighting this includes the use of CFLs and residential luminaires.
Acceptance Testing - per section 10.3.1.1.3 of the Standard, certain,lighting equipment is required to have acceptance testing
Commissioning - per section 10.3.1.2 of the Standard, lighting controls and shading controls are specifically included in the requirement for the commissioning of buildings over 5,000 sq.ft.