Fire Sprinkler Research Articles

Moisture expansion of ceramic whiteware

Automatic fire sprinklers use a heat sensitive element such as a glass bulb or fusible link to respond to the heat from a fire. The response of commercial fire sprinkler glass bulbs has been extensively characterised in convection-dominated dry gas flows but in real fires there may be more factors that influence the heat transfer to the bulbs such as radiation from the fire or cooling from adjacent sprinkler sprays. The time of activation is the only indication of the thermal response of typical commercial fire sprinklers using glass bulbs to a fire, but direct temperature measurement using a modified proxy may provide a better understanding of how sprinklers respond in a complex environment. Modified glass bulbs have been created that allow a thermocouple to be inserted in the bulb for direct temperature measurement. In this paper, the thermal response of sprinklers with these modified bulbs has been observed in hot-air wind tunnel plunge experiments and full scale room fire experiments. At the time of activation the measured temperature of the modified sprinklers was found to be higher than the nominal activation temperature specification for the unmodified sprinklers. For the compartment fires, a thermal response model generally predicted longer sprinkler activation times based on ceiling jet temperature and velocity measurements than was observed experimentally.

Equitable Charges for Sprinkler Fire Protection Service

though the income from private fire protection in the average water works constitutes only 1 or 2 percent of the total income, quite frequently in rate hearings before regulatory bodies, there is as much evidence introduced relative to sprinkler rates as with respect to all other items of the schedule. It would seem that little controversy should arise over charges for a service which produces savings to the consumers having the service which are usually very much greater than the payments made to the water department which makes the service possible. Automatic sprinkler fire protection service is of direct value to those making the installation, is often of indirect value to adjoining properties and to a smaller extent, is also of value to the water utility and the community as a whole. The owner of the property who has installed an automatic sprinkler fire protection system profits through a reduction in his insurance rates usually in amounts varying from 60 to 80 percent of the total premium. To secure this reduction in premium, he is required to expend for the installation of the automatic sprinkler system an amount usually varying between 1 and 4 percent of the building cost. The annual cost to the owner, including therein the fixed charges for interest, depreciation, etc. on the cost of installation, is from 0.1 to 0.5 percent of the building cost. This annual expenditure, as before stated, results in saving from two-thirds to threefourths of the insurance bill. The cost of installing a sprinkler system is usually repaid in a very few years by reduced insurance premiums. Adjoining properties benefit from the installation made, due to the fact that the risk of conflagration spreading from the sprinklered

Charges for Automatic Fire Sprinkler System

This petition was denied by the Commission because of the wellestablished fact that the automatic spinkler charge is nothing more nor less than a ready-to-serve charge which is included in the rate schedule of every public utility furnishing electric and water service in the State of Indiana. The principal averment of the petitioners was, that the charge for this water connection imposes an additional burden on the automatic sprinkler owners and is a discriminatory tax; and that it tends to destroy the interest of the average property owner in equipping his property for the reduction of fire peril. Petitioners introduced considerable evidence to show the unreasonableness of the automatic spinkler charge herein complained of, but also set forth the fact that the fire hazard in factories is greatly reduced by the automatic sprinkler system; that properties adjacent to factories having such automatic fire sprinkler systems receive the benefit of additional protection; and that such systems result in benefit to labor by making possible its continuous employment, because of the preservation of the factories so equipped. However, petitioners failed to make reference to the fact that no device has any merit or would be of any benefit whatever without an abundant water supply ready with sufficient pressure to force it wherever and whenever needed. Evidence was also introduced by petitioners to show that inasmuch as very little water is used in this service, no expense is attached to