The US Securities and Exchange Commission proposed rules aimed at preventing losses for money-market fund investors after last year’s collapse of the Reserve Primary Fund triggered a run on the $3.8 trillion industry.

The agency’s commissioners voted 5-0 to seek comment on a plan to require that funds hold more liquid assets and cut the average maturity of securities in their portfolios. The proposals resemble recommendations made in March by the Investment Company Institute, an industry group.

The SEC has been considering rules for money-market funds since the $62.5 billion Reserve Primary was forced to liquidate amid losses on debt issued by Lehman Brothers Holdings Inc., the investment bank that failed in September.

The agency is trying to reduce the chances of funds’ values falling below $1 a share and make them a more stable source of financing for US firms.