According to a 1980 Bureau of Labor Statistics study, 70% of head injuries to construction workers result from blows to areas other than the top of the head. Yet the American National Standards Institute requires only vertical impact resistance.

Recently, several manufacturers have designed hard hats with increased resistance to side impacts. The hats incorporate such features as an expanded-polystyrene-foam liner, a corrugated plastic ring and deformable fins. Though the new hats are a bit more expensive and, in some cases, heavier than conventional hard hats, the extra protection they provide to the wearer more than makes up for these disadvantages.