ADMINISTRATIVE MEMORANDUM
COUNTY OF SAN MATEO
NUMBER: B-28
SUBJECT: Guidelines for Indoor Thermal Comfort and Ventilation
RESPONSIBLE DEPARTMENT: County Manager
APPROVED: John L. Maltbie, County Manager
DATE: January 26, 2015
This Administrative Memorandum rescinds and replaces Administrative Memorandum B-28, dated July 28, 2003, revising the policy of Guidelines for Indoor Thermal Comfort and Ventilation.
Purpose
This memorandum establishes an acceptable temperature range for buildings with Heating, Ventilating and Air Conditioning (HVAC) temperature controlled areas.
Background
The cost of gas and electricity used to heat, cool, light and power county buildings and equipment represent approximately forty (40) percent of the facility charges that Departments pay.
A substantial amount of energy and cost savings can be realized by establishing an acceptable range for buildings with Heating, Ventilating and Air Conditioning (HVAC) controlled areas. Savings can vary dependent on building and systems conditions.
Discussion
The County Manager has determined the following temperatures to be considered “acceptable” and within the framework of conserving energy while providing a comfortable work environment.
Acceptable temperature range: 68° – 76.°
As individual buildings and HVAC systems vary, so can their ability to maintain these ranges. within the same building or floor can have differing ambient temperatures. In winter, er areas can be warmer than spaces along exterior walls, particularly exterior walls with operable windows. How individuals dress can have a lot to do with personal comfort. Some individuals will tend to be warmer, or colder, than others in the same area. It is also important that ecognize their comfort level and dress appropriately for the season or particular condition.
If the HVAC system is not operating within the acceptable range in temperature-controlled areas, report the problem to the Facilities Maintenance or Engineering Office or local maintenance staff. If the temperature is within the acceptable range and operating properly, no action will be taken. The temperature in an area may fluctuate within the acceptable range many times during the day. Keeping doors and operable windows open in temperature controlled spaces can contribute significantly to such fluctuation.
Note that use of personal fans and heaters in close proximity to thermostats can interfere with temperature control systems. A personal heater too close to a thermostat will cause it to sense that the space is too hot, thus sending even more cooling through the system. A personal fan may cause a nearby air conditioning thermostat to falsely sense that the room is too cool, consequently increasing warm air supplied to the room.
Therefore, portable electric heaters or fans may only be used in County facilities when specifically required by occupants due to medical conditions, failure of the building heating, ventilating, or air- conditioning systems, or when building heating, ventilating, or air-conditioning systems are not able to maintain appropriate temperature ranges. The Facilities Manager through the Department of Public Works must approve exceptions to this policy.