The type-1 phaser is the smallest, most basic weapon carried by Starfleet and other Federation personnel. Type 1 phasers are typically carried when it would be necessary/advisable to be armed but appear to be unarmed such as on diplomatic missions where there is the danger of violence or "undercover" work.
With 8 different settings ranging from stun to heat through disruption to disintegration the type 1 phaser is more than suitable for use in low risk situations. A low power variant of the Type-1 was also available, this variant only had three settings; light to heavy stun.
Setting 1 - Light Stun This setting is calibrated for base humanoid physiology, and causes temporary central nervous system (CNS) impairment resulting in unconsciousness for up to 5 minutes. Higher levels of reversible damage to the CNS result from repeated long exposures Standard composite structural materials of median-density (consisting typically of multiple layers of tritanium, duranium, cortenite, lignin, and lithium-silicon-carbon 372) are not permanently affected, although some warming (from vibration) will be detected
Setting 2 - Medium Stun Base-type humanoids remain unconscious for up to 15 minutes. Resistant humanoid types will be rendered unconscious for up to 5 minutes. Long exposures produce low levels of reversible damage to the CNS and epithelial layers. Structural materials are not affected, though higher levels of vibrational warming are evident
Setting 3 - Heavy Stun Base-type humanoids will enter a deep unconsciousness for up to 1 hour. Resistant bioforms will be rendered unconscious for approximately 15 minutes. Single discharges raise 1cc of liquid water by 100ºC. Structural samples experience significant levels of thermal radiation
Setting 4 - Low Thermal Effects Base-type humanoids experience extensive CNS damage and epidermal trauma Structural materials exhibit visible thermal shock. Discharges of longer than five seconds produce deep heat storage effects within metal alloys
Setting 5 - High Thermal Effects Humanoid tissues experience severe burn effects but (due to water content) deeper epithelial layers will not char. Simple personal forcefields are penetrated after five seconds. Large fields as used by Away Teams will not be affected
Setting 6 - Light Disruption Effects Organic tissues and structural materials exhibit comparable penetration and molecular damage as high energy causes matter to undergo rapid dissociation. The 'familiar' thermal effects begin to decrease at this level
Setting 7 - Moderate Disruption Effects Organic tissue damage causes immediate cessation of life processes as disruption effects become widespread.
Setting 8 - Medium Disruption Effects Cascading disruption forces cause humanoid organisms to vapourise, as 50% of affected matter transitions out of the continuum. All unprotected matter is affected and penetrated according to depth and time of application.