Fire smoke

Check for plant integrity/flammable leaks periodically or continuously on-line, as appropriate Install appropriate fire/smoke detection, audible alarms Provide adequate fire suppression systems Deal with mishaps such as spillage immediately... 

Elues Passages for services or other ducts must be adequately fire-stopped to prevent their acting as flues for fire/smoke transmission... 

Fire Smoke detectors, intumescent coatings/seals... 

Install appropriate fire/smoke detection, audible alarms... 

As these strategies are brought to fruition, there remains one related issue the determination of a smoke s potential harm per mass of material burned, i.e., the toxic potency of smoke. Accurate measurement of this key characteristic of fire smoke permits a more quantitative determination of the fire s toxic hazard which includes other factors as discussed below. Toxic potency assessment also tells us whether a small fire will produce smoke so toxic that only a small amount will kill. The presence of such "supertoxicants" has been a major topic of discussion within the fire community. 

All fire smoke is toxic. In the past two decades, a sizable research effort has resulted in the development of over twenty methods to measure the toxic potency of those fire smokes (6). Some methods have been based on determinations of specific chemical species alone. Values for the effect (e.g., lethality) of these chemicals on humans are obtained from (a) extrapolation from preexisting, lower concentration human exposure data or from (b) interpretation of autopsy data from accident and suicide victims. The uncertainty in these methods is large since ... 

LEVIN GANN Toxic Potency of Fire Smoke... 

It is well known that hydrogen cyanide can be liberated during combustion of nitrogen containing polymers such as wool, silk, polyacrylonitrile, or nylons (1, 2). Several investigators have reported cyanide levels in smoke from a variety of fires (3, 4, 5). The levels reported are much below the lethal levels. Thus the role of cyanide in fire deaths would seem to be quite low. However, as early as 1966 the occurence of cyanide in the blood (above normal values) of fire victims was reported (6). Since then many investigators have reported elevated cyanide levels in fire victims (7-13). However, it has been difficult to arrive at a cyanide blood level which can be considered lethal in humans. In this report the results of cyanide analysis in blood of fire victims are reported as well as the possibility that cyanide may, in some cases, be more important than carbon monoxide as the principal toxicant in fire smoke. 

With so many other toxicants present in fire smoke there must be some which reduce the toxicity of HCN. Similar findings were also found for cynomolgus monkeys exposed to smoke containing HCN vs. HCN alone (14). 

Jones, W. W., A Model for the Transport of Fire. Smoke and Toxic Gases (FASTI NBSIR 84-2934, Natl Bur. Stands (September), 1984. 

McMahon, C.K. and S.N. Tsoukalas. 1978. Polynuclear aromatic hydrocarbons in forest fire smoke. Pages 61-73 in P.W. Jones and R.I. Freudenthal (eds.). Carcinogenesis —A Comprehensive Survey. Vol. 3. Polynuclear National Symposium on Analysis, Chemistry, and Biology. Raven Press, New York. 

Sheet Metal and Air Conditioning Contractors National Association, Inc., (SMACNA), Fire. Smoke and Radiation Damper Installation Guide for HVAC Systems. Fourth Edition, SMACNA, Chantilly, VA, 1993. 

When and emergency egress route is provided it should be protected from the effects of fire and smoke or the personnel equipped with a means to protect themselves when transversing it. It has been shown that people are reluctant to enter into smoke that reduces visibility to less than 10 meters (33 ft.), even when it is not hazardous to do so. Where the effects of fire, smoke and explosions are likely emergency egress route, it is the same as not providing an egress route. 

In contrast to systems that are set up to transmit local only alarms when the sensors are triggered, systems can also be set up to transmit signals to a central location, such as to a control room or guard post at the utility, or to a police or fire station. Most fire/smoke alarms are set up to signal both at the location of the event and at a fire station or central monitoring station. Many insurance companies require that facilities install certified systems that include alarm communication to a central station. For example, systems certified by the Underwriters Laboratory (UL) require that the alarm be reported to a central monitoring station. 

Table 9.7. Fire/smoke/heat detection sensors ...

Polyetherimides are inherently fire resistant, with oxygen indices superior to 47 and a UL94 VO rating. Compounding can improve these performances and certain grades reach an oxygen index of 50. In the event of fire, smoke emissions are low. 

Because of the dead-air space that might be missed by turbulent hot air bouncing around above a fire, smoke detectors should be installed either on the ceiling at least four inches from the nearest wall, or high on a wall at least four, but no further than twelve, inches from the ceiling. 

Where personnel take refuge in a building from an outdoor fire, smoke infiltration into a building may be a concern. A methodology is available to estimate this impact based on the concentration of the material present outside of the building, the building ventilation rate, and the time of exposure (SINTEF, 1997 Fees, 1996). 

Fire detectors generally fall within one of three categories heat, smoke, and flame. Heat detectors work by sensing the heat from a fire. Smoke detectors sense the combustion products from the fire. Flame detectors identify flame by sensing the IR or UV light it emits. 

Sparks, etc. Sparks from mechanical tools and equipment, hot ashes from smoking, unprotected extension lights, boilers and furnaces, backfire from gasoline engines, are all potential causes of fire. Smoking should be prohibited in areas where flammable liquids are stored or are used in the open. All equipment in such areas should be maintained in first class condition. Wherever possible, spark-proof or non-sparking tools and materials should be used... 

Confirmed Fire/Smoke Condition High-Rise Building... 

BMIs and maleimide-terminated prepolymers have been considered for systems with improved Fire, Smoke and Toxicity properties. Of particular interest are phosphorous-containing bismaleimides because they provide high Limiting Oxigen Index (LOI) values (30). 3,3 -bis(maleimidophenyl) methyl phosphine oxide is such a compound (Fig. 7). 

ABD 0031 Airbus Directives (ABD) and Procedures for Fire-Smoke-Toxicity (FST). Airbus Industries. 

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