§ 299. Ventilation, heating and humidity. 1. Every work room in a
factory shall be provided with proper and sufficient means of
ventilation, natural or mechanical or both, as may be necessary, and
there shall be maintained therein proper and sufficient ventilation and
proper degrees of temperature and humidity at all times during the
working hours. If owing to the nature of the manufacturing process
carried on in the factory work room excessive heat be created therein,
there shall be provided, maintained and operated such special means or
appliances as may be required to reduce such excessive heat.

2. All machinery creating dust or impurities in quantities tending to
injure the health of employees shall be equipped with proper hoods and
pipes connected to an exhaust fan of sufficient capacity and power to
remove such dusts or impurities; such fan shall be kept running
constantly while such machinery is in use. If the board decides that
such apparatus is unnecessary for the health and welfare of the
employees, or that other means of protection may be provided to
safeguard the health and welfare of the employees against such injurious
dusts or impurities, it may adopt rules excepting such machinery from
the operation of this subdivision, or prescribing such requirements as
will effectuate the intent of this subdivision.

3. If dust, gases, fumes, vapors, fibers or other impurities are
generated or released in the course of the business carried on in any
workroom of a factory, in quantities tending to injure the health of the
employees, suction devices shall be provided which shall remove such
impurities from the workroom, at their point of origin where
practicable, by means of proper hoods connected to conduits and exhaust
fans. Such fans shall be kept running constantly while the impurities
are being generated or released.

4. The board shall make rules for and fix standards of ventilation,
temperature and humidity in factories and shall prescribe the special
means, if any, required for removing impurities or for reducing
excessive heat, and the machinery, apparatus or appliances to be used
for any of said purposes, and the construction, equipment, maintenance
and operation thereof.

5. If any requirement of this section or any rule adopted thereunder
be not complied with, the commissioner shall issue an order directing
compliance therewith within thirty days after the service thereof. He
may in such order require plans and specifications to be filed. In such
case, before providing or making any change or alteration in any
machinery or apparatus for any of the purposes specified in this
section, the person upon whom such order is served shall file with the
commissioner plans and specifications therefor and shall obtain his
approval of the same.