Weight is expressed in g/m². This measurement will affect the weight of the finished garment and its thickness. Heat will take longer to get through a thicker garment so it will provide a higher protection level.
Weight also affects wearer comfort, so there has to be a compromise between what is acceptable to wear due to the work environment and the protection required due to the hazards present. It is worth noting that a garment that is heavy and induces heat stress, encourages a wearer to undo the fasteners and roll up sleeves. This lowers protection levels, so in these cases, it may be better to issue a lighter garment that people will wear correctly.
The weave is the pattern the yarns follow to make up the fabric. It is given a name such as twill, plain or matt etc.
The weave can have an impact on the ability of the fabric to shed liquids or molten solids and to the actual break open strength of the fabric.
In terms of arc protection , a twill weave usually produces the best results.